如何提取 Access (.mdb) 数据库的架构?

发布于 2024-07-15 11:35:38 字数 70 浏览 8 评论 0原文

我正在尝试提取 .mdb 数据库的架构,以便我可以在其他地方重新创建数据库。

我怎样才能完成这样的事情呢?

I am trying to extract the schema of an .mdb database, so that I can recreate the database elsewhere.

How can I pull off something like this?

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评论(10

贱人配狗天长地久 2024-07-22 11:35:39

查看 docmd.TransferDatabase 命令。 对于需要复制数据结构的构建集成来说,这可能是您的最佳选择

Check out the docmd.TransferDatabase command. It is probably your best bet for build integration that needs to replicate the data structure

黯淡〆 2024-07-22 11:35:39

比较他们
http://home.gci.net/~mike-noel/ CompareEM-LITE/CompareEM.htm
将愉快地生成重新创建 MDB 所需的 VBA 代码。 或者创建两个 MDB 之间差异的代码,以便您可以对现有的 BE MDB 进行版本升级。 这有点奇怪但有效。 请注意,它不支持新的 ACE (Access2007) ACCDB 等格式。

我用它所有的时间。

(OneDayWhen 的编辑有三分之一正确,三分之二错误。)

Compare'Em
http://home.gci.net/~mike-noel/CompareEM-LITE/CompareEM.htm
will happily generate the VBA code need to recreate an MDB. Or the code to create the differences between two MDBs so you can do a version upgrade of the already existing BE MDB. It's a bit quirky but works. Note it does not support the new ACE (Access2007) ACCDB etc formats.

I use it all the time.

(OneDayWhen's edit was one third right and two thirds wrong.)

绮筵 2024-07-22 11:35:39

在 Access 中执行 DDL 脚本/查询很困难。 这是可以完成的,但您最好只创建数据库的副本 - 删除所有数据并压缩它。 然后使用该副本在其他地方重新创建数据库。

It's hard to do DDL scripts / queries in Access. It can be done but you'd be better off just creating a copy of the database - deleting all the data and compacting it. Then use a copy of this for recreating the database elsewhere.

落墨 2024-07-22 11:35:39

非常有帮助的帖子!

我修改了脚本来生成 SQL Server 的数据定义语言。 我认为它可能对某人有用,所以我分享它。 我遇到的一个问题是 VBS 脚本提取表中的所有字段作为索引。 我还不确定如何解决这个问题,所以我只提取第一个字段。 这适用于大多数主键。 最后,并不是所有的数据类型都得到了证明,但我想我已经得到了大部分。

Option Compare Database


Function exportTableDefs()

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\temp\Schema.txt")

    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" And Left(tdf.Name, 1) <> "~" Then
            strSQL = "CREATE TABLE [" & tdf.Name & "] (" & vbCrLf

            strFlds = ""

            For Each fld In tdf.Fields

                strFlds = strFlds & ",[" & fld.Name & "] "

                Select Case fld.Type

                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "varchar (" & fld.SIZE & ")"

                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "bigint"
                        Else
                            strFlds = strFlds & "int IDENTITY(1,1)"
                        End If

                    Case dbBoolean
                        strFlds = strFlds & "bit"

                    Case dbByte
                        strFlds = strFlds & "tinyint"

                    Case dbInteger
                        strFlds = strFlds & "int"

                    Case dbCurrency
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbSingle
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbDouble
                        strFlds = strFlds & "Float"

                    Case dbDate
                        strFlds = strFlds & "DateTime"

                    Case dbBinary
                        strFlds = strFlds & "binary"

                    Case dbLongBinary
                        strFlds = strFlds & "varbinary(max)"

                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "varbinary(max)"
                        Else
                            strFlds = strFlds & "?"
                        End If

                    Case dbGUID
                        strFlds = strFlds & "?"
                    Case Else
                        strFlds = strFlds & "?"

                End Select
                strFlds = strFlds & vbCrLf

            Next

            ''  get rid of the first comma
            strSQL = strSQL & Mid(strFlds, 2) & " )" & vbCrLf

            f.WriteLine strSQL

            strSQL = ""

            'Indexes
            For Each ndx In tdf.Indexes

                If Left(ndx.Name, 1) <> "~" Then
                    If ndx.Primary Then
                        strSQL = "ALTER TABLE " & tdf.Name & " ADD  CONSTRAINT " & tdf.Name & "_primary" & " PRIMARY KEY CLUSTERED ( " & vbCrLf
                    Else
                        If ndx.Unique Then
                            strSQL = "CREATE UNIQUE NONCLUSTERED INDEX "
                        Else
                            strSQL = "CREATE NONCLUSTERED INDEX "
                        End If
                        strSQL = strSQL & "[" & tdf.Name & "_" & ndx.Name & "] ON [" & tdf.Name & "] ("
                    End If

                    strFlds = ""

                    '''  Assume that the index is only for the first field.  This will work for most primary keys
                    '''  Not sure how to get just the fields in the index
                    For Each fld In tdf.Fields
                        strFlds = strFlds & ",[" & fld.Name & "] ASC "
                        Exit For
                    Next

                    strSQL = strSQL & Mid(strFlds, 2) & ") "
                End If
            Next
           f.WriteLine strSQL & vbCrLf
        End If
    Next

    f.Close

End Function

Very helpful post!

I have revised the script to generate the data definition language for SQL server. I thought it might be useful to someone, so I'm sharing it. The one problem I ran into is that the VBS script extracts all fields in the table for indexes. I'm not sure how to solve this just yet, so I extract only the first field. This will work for most primary keys. Finally, not all of the data types are proven, but I think I got most of them.

Option Compare Database


Function exportTableDefs()

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\temp\Schema.txt")

    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" And Left(tdf.Name, 1) <> "~" Then
            strSQL = "CREATE TABLE [" & tdf.Name & "] (" & vbCrLf

            strFlds = ""

            For Each fld In tdf.Fields

                strFlds = strFlds & ",[" & fld.Name & "] "

                Select Case fld.Type

                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "varchar (" & fld.SIZE & ")"

                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "bigint"
                        Else
                            strFlds = strFlds & "int IDENTITY(1,1)"
                        End If

                    Case dbBoolean
                        strFlds = strFlds & "bit"

                    Case dbByte
                        strFlds = strFlds & "tinyint"

                    Case dbInteger
                        strFlds = strFlds & "int"

                    Case dbCurrency
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbSingle
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbDouble
                        strFlds = strFlds & "Float"

                    Case dbDate
                        strFlds = strFlds & "DateTime"

                    Case dbBinary
                        strFlds = strFlds & "binary"

                    Case dbLongBinary
                        strFlds = strFlds & "varbinary(max)"

                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "varbinary(max)"
                        Else
                            strFlds = strFlds & "?"
                        End If

                    Case dbGUID
                        strFlds = strFlds & "?"
                    Case Else
                        strFlds = strFlds & "?"

                End Select
                strFlds = strFlds & vbCrLf

            Next

            ''  get rid of the first comma
            strSQL = strSQL & Mid(strFlds, 2) & " )" & vbCrLf

            f.WriteLine strSQL

            strSQL = ""

            'Indexes
            For Each ndx In tdf.Indexes

                If Left(ndx.Name, 1) <> "~" Then
                    If ndx.Primary Then
                        strSQL = "ALTER TABLE " & tdf.Name & " ADD  CONSTRAINT " & tdf.Name & "_primary" & " PRIMARY KEY CLUSTERED ( " & vbCrLf
                    Else
                        If ndx.Unique Then
                            strSQL = "CREATE UNIQUE NONCLUSTERED INDEX "
                        Else
                            strSQL = "CREATE NONCLUSTERED INDEX "
                        End If
                        strSQL = strSQL & "[" & tdf.Name & "_" & ndx.Name & "] ON [" & tdf.Name & "] ("
                    End If

                    strFlds = ""

                    '''  Assume that the index is only for the first field.  This will work for most primary keys
                    '''  Not sure how to get just the fields in the index
                    For Each fld In tdf.Fields
                        strFlds = strFlds & ",[" & fld.Name & "] ASC "
                        Exit For
                    Next

                    strSQL = strSQL & Mid(strFlds, 2) & ") "
                End If
            Next
           f.WriteLine strSQL & vbCrLf
        End If
    Next

    f.Close

End Function
萌能量女王 2024-07-22 11:35:39

罗兰上面的答案(由托比亚斯编辑)对我有用,但有一些变化。 首先我解决了查找主键中所有字段的问题; 那么索引sql代码写入文件的位置是错误的:
选项比较数据库

Function exportTableDefs()

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\temp\Schema.txt")

    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" And Left(tdf.Name, 1) <> "~" Then
            strSQL = "CREATE TABLE [" & tdf.Name & "] (" & vbCrLf

            strFlds = ""

            For Each fld In tdf.Fields

                strFlds = strFlds & ",[" & fld.Name & "] "

                Select Case fld.Type

                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "varchar (" & fld.SIZE & ")"

                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "bigint"
                        Else
                            strFlds = strFlds & "int IDENTITY(1,1)"
                        End If

                    Case dbBoolean
                        strFlds = strFlds & "bit"

                    Case dbByte
                        strFlds = strFlds & "tinyint"

                    Case dbInteger
                        strFlds = strFlds & "int"

                    Case dbCurrency
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbSingle
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbDouble
                        strFlds = strFlds & "Float"

                    Case dbDate
                        strFlds = strFlds & "DateTime"

                    Case dbBinary
                        strFlds = strFlds & "binary"

                    Case dbLongBinary
                        strFlds = strFlds & "varbinary(max)"

                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "varbinary(max)"
                        Else
                            strFlds = strFlds & "?"
                        End If

                    Case dbGUID
                        strFlds = strFlds & "?"
                    Case Else
                        strFlds = strFlds & "?"

                End Select
                strFlds = strFlds & vbCrLf

            Next

            ''  get rid of the first comma
            strSQL = strSQL & Mid(strFlds, 2) & " )" & vbCrLf

            f.WriteLine strSQL

            strSQL = ""

            'Indexes
            For Each ndx In tdf.Indexes

                If Left(ndx.Name, 1) <> "~" Then
                    If ndx.Primary Then
                        strSQL = "ALTER TABLE " & tdf.Name & " ADD  CONSTRAINT " & tdf.Name & "_primary" & " PRIMARY KEY CLUSTERED ( " & vbCrLf
                    Else
                        If ndx.Unique Then
                            strSQL = "CREATE UNIQUE NONCLUSTERED INDEX "
                        Else
                            strSQL = "CREATE NONCLUSTERED INDEX "
                        End If
                        strSQL = strSQL & "[" & tdf.Name & "_" & ndx.Name & "] ON [" & tdf.Name & "] ("
                    End If

                    strFlds = ""

                    '''  use the ndx collection rather than tdf
                    For Each fld In ndx.Fields
                        strFlds = strFlds & ",[" & fld.Name & "] ASC "
                        Exit For
                    Next

                    strSQL = strSQL & Mid(strFlds, 2) & ") "
                End If
                ''' write to file for each iteration of the loop to get multiple indexes
                f.WriteLine strSQL & vbCrLf
            Next
        End If
    Next

    f.Close

End Function

Roland's answer above (edited by Tobias) worked for me but with a couple of changes. Firstly I solved the issue of finding all fields in the primary key; then the writing to file of the index sql code was in the wrong place:
Option Compare Database

Function exportTableDefs()

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\temp\Schema.txt")

    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" And Left(tdf.Name, 1) <> "~" Then
            strSQL = "CREATE TABLE [" & tdf.Name & "] (" & vbCrLf

            strFlds = ""

            For Each fld In tdf.Fields

                strFlds = strFlds & ",[" & fld.Name & "] "

                Select Case fld.Type

                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "varchar (" & fld.SIZE & ")"

                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "bigint"
                        Else
                            strFlds = strFlds & "int IDENTITY(1,1)"
                        End If

                    Case dbBoolean
                        strFlds = strFlds & "bit"

                    Case dbByte
                        strFlds = strFlds & "tinyint"

                    Case dbInteger
                        strFlds = strFlds & "int"

                    Case dbCurrency
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbSingle
                        strFlds = strFlds & "decimal(10,2)"

                    Case dbDouble
                        strFlds = strFlds & "Float"

                    Case dbDate
                        strFlds = strFlds & "DateTime"

                    Case dbBinary
                        strFlds = strFlds & "binary"

                    Case dbLongBinary
                        strFlds = strFlds & "varbinary(max)"

                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "varbinary(max)"
                        Else
                            strFlds = strFlds & "?"
                        End If

                    Case dbGUID
                        strFlds = strFlds & "?"
                    Case Else
                        strFlds = strFlds & "?"

                End Select
                strFlds = strFlds & vbCrLf

            Next

            ''  get rid of the first comma
            strSQL = strSQL & Mid(strFlds, 2) & " )" & vbCrLf

            f.WriteLine strSQL

            strSQL = ""

            'Indexes
            For Each ndx In tdf.Indexes

                If Left(ndx.Name, 1) <> "~" Then
                    If ndx.Primary Then
                        strSQL = "ALTER TABLE " & tdf.Name & " ADD  CONSTRAINT " & tdf.Name & "_primary" & " PRIMARY KEY CLUSTERED ( " & vbCrLf
                    Else
                        If ndx.Unique Then
                            strSQL = "CREATE UNIQUE NONCLUSTERED INDEX "
                        Else
                            strSQL = "CREATE NONCLUSTERED INDEX "
                        End If
                        strSQL = strSQL & "[" & tdf.Name & "_" & ndx.Name & "] ON [" & tdf.Name & "] ("
                    End If

                    strFlds = ""

                    '''  use the ndx collection rather than tdf
                    For Each fld In ndx.Fields
                        strFlds = strFlds & ",[" & fld.Name & "] ASC "
                        Exit For
                    Next

                    strSQL = strSQL & Mid(strFlds, 2) & ") "
                End If
                ''' write to file for each iteration of the loop to get multiple indexes
                f.WriteLine strSQL & vbCrLf
            Next
        End If
    Next

    f.Close

End Function
回心转意 2024-07-22 11:35:38

用VBA 可以做一些事情。 例如,这里是为具有本地表的数据库创建脚本的开始。

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String
Dim strCn As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\Docs\Schema.txt")
    
    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" Then
            strSQL = "strSQL=""CREATE TABLE [" & tdf.Name & "] ("
            
            strFlds = ""
            
            For Each fld In tdf.Fields
                
                strFlds = strFlds & ",[" & fld.Name & "] "
                
                Select Case fld.Type
                
                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "Text (" & fld.Size & ")"
                    
                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "Long"
                        Else
                            strFlds = strFlds & "Counter"
                        End If
    
                    Case dbBoolean
                        strFlds = strFlds & "YesNo"
    
                    Case dbByte
                        strFlds = strFlds & "Byte"
                        
                    Case dbInteger
                        strFlds = strFlds & "Integer"
                    
                    Case dbCurrency
                        strFlds = strFlds & "Currency"
            
                    Case dbSingle
                        strFlds = strFlds & "Single"
            
                    Case dbDouble
                        strFlds = strFlds & "Double"
            
                    Case dbDate
                        strFlds = strFlds & "DateTime"
            
                    Case dbBinary
                        strFlds = strFlds & "Binary"
            
                    Case dbLongBinary
                        strFlds = strFlds & "OLE Object"
                        
                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "Memo"
                        Else
                            strFlds = strFlds & "Hyperlink"
                        End If
                        
                    Case dbGUID
                        strFlds = strFlds & "GUID"
                        
                End Select
            
            Next
    
            strSQL = strSQL & Mid(strFlds, 2) & " )""" & vbCrLf & "Currentdb.Execute strSQL"
            
            f.WriteLine vbCrLf & strSQL
        
            'Indexes
            For Each ndx In tdf.Indexes
            
                If ndx.Unique Then
                    strSQL = "strSQL=""CREATE UNIQUE INDEX "
                Else
                    strSQL = "strSQL=""CREATE INDEX "
                End If
                
                strSQL = strSQL & "[" & ndx.Name & "] ON [" & tdf.Name & "] ("
                
                strFlds = ""

                For Each fld In tdf.Fields
                    strFlds = strFlds & ",[" & fld.Name & "]"
                Next
                    
                strSQL = strSQL & Mid(strFlds, 2) & ") "
                
                strCn = ""
                
                If ndx.Primary Then
                    strCn = " PRIMARY"
                End If
                
                If ndx.Required Then
                    strCn = strCn & " DISALLOW NULL"
                End If
                
                If ndx.IgnoreNulls Then
                    strCn = strCn & " IGNORE NULL"
                End If
                
                If Trim(strCn) <> vbNullString Then
                    strSQL = strSQL & " WITH" & strCn & " "
                End If
                
                f.WriteLine vbCrLf & strSQL & """" & vbCrLf & "Currentdb.Execute strSQL"
            Next
        End If
    Next
        
    f.Close

It is possible to do a little with VBA. For example, here is a start on creating script for a database with local tables.

Dim db As Database
Dim tdf As TableDef
Dim fld As DAO.Field
Dim ndx As DAO.Index
Dim strSQL As String
Dim strFlds As String
Dim strCn As String

Dim fs, f

    Set db = CurrentDb

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set f = fs.CreateTextFile("C:\Docs\Schema.txt")
    
    For Each tdf In db.TableDefs
        If Left(tdf.Name, 4) <> "Msys" Then
            strSQL = "strSQL=""CREATE TABLE [" & tdf.Name & "] ("
            
            strFlds = ""
            
            For Each fld In tdf.Fields
                
                strFlds = strFlds & ",[" & fld.Name & "] "
                
                Select Case fld.Type
                
                    Case dbText
                        'No look-up fields
                        strFlds = strFlds & "Text (" & fld.Size & ")"
                    
                    Case dbLong
                        If (fld.Attributes And dbAutoIncrField) = 0& Then
                            strFlds = strFlds & "Long"
                        Else
                            strFlds = strFlds & "Counter"
                        End If
    
                    Case dbBoolean
                        strFlds = strFlds & "YesNo"
    
                    Case dbByte
                        strFlds = strFlds & "Byte"
                        
                    Case dbInteger
                        strFlds = strFlds & "Integer"
                    
                    Case dbCurrency
                        strFlds = strFlds & "Currency"
            
                    Case dbSingle
                        strFlds = strFlds & "Single"
            
                    Case dbDouble
                        strFlds = strFlds & "Double"
            
                    Case dbDate
                        strFlds = strFlds & "DateTime"
            
                    Case dbBinary
                        strFlds = strFlds & "Binary"
            
                    Case dbLongBinary
                        strFlds = strFlds & "OLE Object"
                        
                    Case dbMemo
                        If (fld.Attributes And dbHyperlinkField) = 0& Then
                            strFlds = strFlds & "Memo"
                        Else
                            strFlds = strFlds & "Hyperlink"
                        End If
                        
                    Case dbGUID
                        strFlds = strFlds & "GUID"
                        
                End Select
            
            Next
    
            strSQL = strSQL & Mid(strFlds, 2) & " )""" & vbCrLf & "Currentdb.Execute strSQL"
            
            f.WriteLine vbCrLf & strSQL
        
            'Indexes
            For Each ndx In tdf.Indexes
            
                If ndx.Unique Then
                    strSQL = "strSQL=""CREATE UNIQUE INDEX "
                Else
                    strSQL = "strSQL=""CREATE INDEX "
                End If
                
                strSQL = strSQL & "[" & ndx.Name & "] ON [" & tdf.Name & "] ("
                
                strFlds = ""

                For Each fld In tdf.Fields
                    strFlds = strFlds & ",[" & fld.Name & "]"
                Next
                    
                strSQL = strSQL & Mid(strFlds, 2) & ") "
                
                strCn = ""
                
                If ndx.Primary Then
                    strCn = " PRIMARY"
                End If
                
                If ndx.Required Then
                    strCn = strCn & " DISALLOW NULL"
                End If
                
                If ndx.IgnoreNulls Then
                    strCn = strCn & " IGNORE NULL"
                End If
                
                If Trim(strCn) <> vbNullString Then
                    strSQL = strSQL & " WITH" & strCn & " "
                End If
                
                f.WriteLine vbCrLf & strSQL & """" & vbCrLf & "Currentdb.Execute strSQL"
            Next
        End If
    Next
        
    f.Close
清欢 2024-07-22 11:35:38

现在这是一个古老的问题,但不幸的是长期存在:(

我认为这段代码可能对其寻求解决方案的其他人有用。它设计为通过 cscript 从命令行运行,因此无需将代码导入到您的 Access 项目中。类似于(并受到启发)来自 Oliver 的代码 如何在 Access 开发中使用版本控制

' Usage:
'  CScript //Nologo ddl.vbs <input mdb file> > <output>
'
' Outputs DDL statements for tables, indexes, and relations from Access file 
' (.mdb, .accdb) <input file> to stdout.  
' Requires Microsoft Access.
'
' NOTE: Adapted from code from "polite person" + Kevin Chambers - see:
' http://www.mombu.com/microsoft/comp-databases-ms-access/t-exporting-jet-table-metadata-as-text-119667.html
'
Option Explicit
Dim stdout, fso
Dim strFile
Dim appAccess, db, tbl, idx, rel

Set stdout = WScript.StdOut
Set fso = CreateObject("Scripting.FileSystemObject")

' Parse args
If (WScript.Arguments.Count = 0) then
    MsgBox "Usage: cscript //Nologo ddl.vbs access-file", vbExclamation, "Error"
    Wscript.Quit()
End if
strFile = fso.GetAbsolutePathName(WScript.Arguments(0))

' Open mdb file
Set appAccess = CreateObject("Access.Application")
appAccess.OpenCurrentDatabase strFile
Set db = appAccess.DBEngine(0)(0)

' Iterate over tables
  ' create table statements
For Each tbl In db.TableDefs
  If Not isSystemTable(tbl) And Not isHiddenTable(tbl) Then
    stdout.WriteLine getTableDDL(tbl)
    stdout.WriteBlankLines(1)

    ' Iterate over indexes
      ' create index statements
    For Each idx In tbl.Indexes
      stdout.WriteLine getIndexDDL(tbl, idx)
    Next

    stdout.WriteBlankLines(2)
  End If
Next

' Iterate over relations
  ' alter table add constraint statements
For Each rel In db.Relations
  Set tbl = db.TableDefs(rel.Table)
  If Not isSystemTable(tbl) And Not isHiddenTable(tbl) Then
    stdout.WriteLine getRelationDDL(rel)
    stdout.WriteBlankLines(1)
  End If
Next

Function getTableDDL(tdef)
Const dbBoolean = 1
Const dbByte = 2
Const dbCurrency = 5
Const dbDate = 8
Const dbDouble = 7
Const dbInteger = 3
Const dbLong = 4
Const dbDecimal = 20
Const dbFloat = 17
Const dbMemo = 12
Const dbSingle = 6
Const dbText = 10
Const dbGUID = 15
Const dbAutoIncrField = 16

Dim fld
Dim sql
Dim ln, a

    sql = "CREATE TABLE " & QuoteObjectName(tdef.name) & " ("
    ln = vbCrLf

    For Each fld In tdef.fields
       sql = sql & ln & " " & QuoteObjectName(fld.name) & " "
       Select Case fld.Type
       Case dbBoolean   'Boolean
          a = "BIT"
       Case dbByte   'Byte
          a = "BYTE"
       Case dbCurrency  'Currency
          a = "MONEY"
       Case dbDate 'Date / Time
          a = "DATETIME"
       Case dbDouble    'Double
          a = "DOUBLE"
       Case dbInteger   'Integer
          a = "INTEGER"
       Case dbLong  'Long
          'test if counter, doesn't detect random property if set
          If (fld.Attributes And dbAutoIncrField) Then
             a = "COUNTER"
          Else
             a = "LONG"
          End If
       Case dbDecimal    'Decimal
          a = "DECIMAL"
       Case dbFloat      'Float
          a = "FLOAT"
       Case dbMemo 'Memo
          a = "MEMO"
       Case dbSingle    'Single
          a = "SINGLE"
       Case dbText 'Text
          a = "VARCHAR(" & fld.Size & ")"
       Case dbGUID 'Text
          a = "GUID"
       Case Else
          '>>> raise error
          MsgBox "Field " & tdef.name & "." & fld.name & _
                " of type " & fld.Type & " has been ignored!!!"
       End Select

       sql = sql & a

       If fld.Required Then _
          sql = sql & " NOT NULL "
       If Len(fld.DefaultValue) > 0 Then _
          sql = sql & " DEFAULT " & fld.DefaultValue

       ln = ", " & vbCrLf
    Next

    sql = sql & vbCrLf & ");"
    getTableDDL = sql

End Function

Function getIndexDDL(tdef, idx)
Dim sql, ln, myfld

    If Left(idx.name, 1) = "{" Then
       'ignore, GUID-type indexes - bugger them
    ElseIf idx.Foreign Then
       'this index was created by a relation.  recreating the
       'relation will create this for us, so no need to do it here
    Else
       ln = ""
       sql = "CREATE "
       If idx.Unique Then
           sql = sql & "UNIQUE "
       End If
       sql = sql & "INDEX " & QuoteObjectName(idx.name) & " ON " & _
             QuoteObjectName(tdef.name) & "( "
       For Each myfld In idx.fields
          sql = sql & ln & QuoteObjectName(myfld.name)
          ln = ", "
       Next
       sql = sql & " )"
       If idx.Primary Then
          sql = sql & " WITH PRIMARY"
       ElseIf idx.IgnoreNulls Then
          sql = sql & " WITH IGNORE NULL"
       ElseIf idx.Required Then
          sql = sql & " WITH DISALLOW NULL"
       End If
       sql = sql & ";"
    End If
    getIndexDDL = sql

End Function

' Returns the SQL DDL to add a relation between two tables.
' Oddly, DAO will not accept the ON DELETE or ON UPDATE
' clauses, so the resulting sql must be executed through ADO
Function getRelationDDL(myrel)
Const dbRelationUpdateCascade = 256
Const dbRelationDeleteCascade = 4096
Dim mytdef
Dim myfld
Dim sql, ln


    With myrel
       sql = "ALTER TABLE " & QuoteObjectName(.ForeignTable) & _
             " ADD CONSTRAINT " & QuoteObjectName(.name) & " FOREIGN KEY ( "
       ln = ""
       For Each myfld In .fields 'ie fields of the relation
          sql = sql & ln & QuoteObjectName(myfld.ForeignName)
          ln = ","
       Next
       sql = sql & " ) " & "REFERENCES " & _
             QuoteObjectName(.table) & "( "
       ln = ""
       For Each myfld In .fields
          sql = sql & ln & QuoteObjectName(myfld.name)
          ln = ","
       Next
       sql = sql & " )"
       If (myrel.Attributes And dbRelationUpdateCascade) Then _
             sql = sql & " ON UPDATE CASCADE"
       If (myrel.Attributes And dbRelationDeleteCascade) Then _
             sql = sql & " ON DELETE CASCADE"
       sql = sql & ";"
    End With
    getRelationDDL = sql
End Function


Function isSystemTable(tbl)
Dim nAttrib
Const dbSystemObject = -2147483646
    isSystemTable = False
    nAttrib = tbl.Attributes
    isSystemTable = (nAttrib <> 0 And ((nAttrib And dbSystemObject) <> 0))
End Function

Function isHiddenTable(tbl)
Dim nAttrib
Const dbHiddenObject = 1
    isHiddenTable = False
    nAttrib = tbl.Attributes
    isHiddenTable = (nAttrib <> 0 And ((nAttrib And dbHiddenObject) <> 0))
End Function

Function QuoteObjectName(str)
    QuoteObjectName = "[" & str & "]"
End Function

如果您还想导出查询定义,这个问题应该有帮助。有点不同因为您通常不会使用普通的 DDL CREATE VIEW foo AS ... 语法创建 querydef,事实上我不确定您可以(?)

但是这是我编写的一小段脚本将查询备份到单独的 .sql 文件(这是用于备份所有前端数据库代码的较大脚本的一部分,请参阅奥利弗的答案 这个问题)。

Dim oApplication
Set oApplication = CreateObject("Access.Application")
oApplication.OpenCurrentDatabase sMyAccessFilePath
oApplication.Visible = False

For Each myObj In oApplication.DBEngine(0)(0).QueryDefs
    writeToFile sExportpath & "\queries\" & myObj.Name & ".sql", myObj.SQL 
Next

Function writeToFile(path, text)
Dim fso, st
  Set fso = CreateObject("Scripting.FileSystemObject")
  Set st = fso.CreateTextFile(path, True)
  st.Write text
  st.Close
End Function

It's an ancient question now, but unfortunately perennial :(

I thought this code may be of use to others looking for solutions. It's designed to be run from the command line via cscript, so no need to import code into your Access project. Similar to (and inspired by) the code from Oliver in How do you use version control with Access development.

' Usage:
'  CScript //Nologo ddl.vbs <input mdb file> > <output>
'
' Outputs DDL statements for tables, indexes, and relations from Access file 
' (.mdb, .accdb) <input file> to stdout.  
' Requires Microsoft Access.
'
' NOTE: Adapted from code from "polite person" + Kevin Chambers - see:
' http://www.mombu.com/microsoft/comp-databases-ms-access/t-exporting-jet-table-metadata-as-text-119667.html
'
Option Explicit
Dim stdout, fso
Dim strFile
Dim appAccess, db, tbl, idx, rel

Set stdout = WScript.StdOut
Set fso = CreateObject("Scripting.FileSystemObject")

' Parse args
If (WScript.Arguments.Count = 0) then
    MsgBox "Usage: cscript //Nologo ddl.vbs access-file", vbExclamation, "Error"
    Wscript.Quit()
End if
strFile = fso.GetAbsolutePathName(WScript.Arguments(0))

' Open mdb file
Set appAccess = CreateObject("Access.Application")
appAccess.OpenCurrentDatabase strFile
Set db = appAccess.DBEngine(0)(0)

' Iterate over tables
  ' create table statements
For Each tbl In db.TableDefs
  If Not isSystemTable(tbl) And Not isHiddenTable(tbl) Then
    stdout.WriteLine getTableDDL(tbl)
    stdout.WriteBlankLines(1)

    ' Iterate over indexes
      ' create index statements
    For Each idx In tbl.Indexes
      stdout.WriteLine getIndexDDL(tbl, idx)
    Next

    stdout.WriteBlankLines(2)
  End If
Next

' Iterate over relations
  ' alter table add constraint statements
For Each rel In db.Relations
  Set tbl = db.TableDefs(rel.Table)
  If Not isSystemTable(tbl) And Not isHiddenTable(tbl) Then
    stdout.WriteLine getRelationDDL(rel)
    stdout.WriteBlankLines(1)
  End If
Next

Function getTableDDL(tdef)
Const dbBoolean = 1
Const dbByte = 2
Const dbCurrency = 5
Const dbDate = 8
Const dbDouble = 7
Const dbInteger = 3
Const dbLong = 4
Const dbDecimal = 20
Const dbFloat = 17
Const dbMemo = 12
Const dbSingle = 6
Const dbText = 10
Const dbGUID = 15
Const dbAutoIncrField = 16

Dim fld
Dim sql
Dim ln, a

    sql = "CREATE TABLE " & QuoteObjectName(tdef.name) & " ("
    ln = vbCrLf

    For Each fld In tdef.fields
       sql = sql & ln & " " & QuoteObjectName(fld.name) & " "
       Select Case fld.Type
       Case dbBoolean   'Boolean
          a = "BIT"
       Case dbByte   'Byte
          a = "BYTE"
       Case dbCurrency  'Currency
          a = "MONEY"
       Case dbDate 'Date / Time
          a = "DATETIME"
       Case dbDouble    'Double
          a = "DOUBLE"
       Case dbInteger   'Integer
          a = "INTEGER"
       Case dbLong  'Long
          'test if counter, doesn't detect random property if set
          If (fld.Attributes And dbAutoIncrField) Then
             a = "COUNTER"
          Else
             a = "LONG"
          End If
       Case dbDecimal    'Decimal
          a = "DECIMAL"
       Case dbFloat      'Float
          a = "FLOAT"
       Case dbMemo 'Memo
          a = "MEMO"
       Case dbSingle    'Single
          a = "SINGLE"
       Case dbText 'Text
          a = "VARCHAR(" & fld.Size & ")"
       Case dbGUID 'Text
          a = "GUID"
       Case Else
          '>>> raise error
          MsgBox "Field " & tdef.name & "." & fld.name & _
                " of type " & fld.Type & " has been ignored!!!"
       End Select

       sql = sql & a

       If fld.Required Then _
          sql = sql & " NOT NULL "
       If Len(fld.DefaultValue) > 0 Then _
          sql = sql & " DEFAULT " & fld.DefaultValue

       ln = ", " & vbCrLf
    Next

    sql = sql & vbCrLf & ");"
    getTableDDL = sql

End Function

Function getIndexDDL(tdef, idx)
Dim sql, ln, myfld

    If Left(idx.name, 1) = "{" Then
       'ignore, GUID-type indexes - bugger them
    ElseIf idx.Foreign Then
       'this index was created by a relation.  recreating the
       'relation will create this for us, so no need to do it here
    Else
       ln = ""
       sql = "CREATE "
       If idx.Unique Then
           sql = sql & "UNIQUE "
       End If
       sql = sql & "INDEX " & QuoteObjectName(idx.name) & " ON " & _
             QuoteObjectName(tdef.name) & "( "
       For Each myfld In idx.fields
          sql = sql & ln & QuoteObjectName(myfld.name)
          ln = ", "
       Next
       sql = sql & " )"
       If idx.Primary Then
          sql = sql & " WITH PRIMARY"
       ElseIf idx.IgnoreNulls Then
          sql = sql & " WITH IGNORE NULL"
       ElseIf idx.Required Then
          sql = sql & " WITH DISALLOW NULL"
       End If
       sql = sql & ";"
    End If
    getIndexDDL = sql

End Function

' Returns the SQL DDL to add a relation between two tables.
' Oddly, DAO will not accept the ON DELETE or ON UPDATE
' clauses, so the resulting sql must be executed through ADO
Function getRelationDDL(myrel)
Const dbRelationUpdateCascade = 256
Const dbRelationDeleteCascade = 4096
Dim mytdef
Dim myfld
Dim sql, ln


    With myrel
       sql = "ALTER TABLE " & QuoteObjectName(.ForeignTable) & _
             " ADD CONSTRAINT " & QuoteObjectName(.name) & " FOREIGN KEY ( "
       ln = ""
       For Each myfld In .fields 'ie fields of the relation
          sql = sql & ln & QuoteObjectName(myfld.ForeignName)
          ln = ","
       Next
       sql = sql & " ) " & "REFERENCES " & _
             QuoteObjectName(.table) & "( "
       ln = ""
       For Each myfld In .fields
          sql = sql & ln & QuoteObjectName(myfld.name)
          ln = ","
       Next
       sql = sql & " )"
       If (myrel.Attributes And dbRelationUpdateCascade) Then _
             sql = sql & " ON UPDATE CASCADE"
       If (myrel.Attributes And dbRelationDeleteCascade) Then _
             sql = sql & " ON DELETE CASCADE"
       sql = sql & ";"
    End With
    getRelationDDL = sql
End Function


Function isSystemTable(tbl)
Dim nAttrib
Const dbSystemObject = -2147483646
    isSystemTable = False
    nAttrib = tbl.Attributes
    isSystemTable = (nAttrib <> 0 And ((nAttrib And dbSystemObject) <> 0))
End Function

Function isHiddenTable(tbl)
Dim nAttrib
Const dbHiddenObject = 1
    isHiddenTable = False
    nAttrib = tbl.Attributes
    isHiddenTable = (nAttrib <> 0 And ((nAttrib And dbHiddenObject) <> 0))
End Function

Function QuoteObjectName(str)
    QuoteObjectName = "[" & str & "]"
End Function

If you are looking to export query definitions as well, this question should help. It's a little different because you don't usually create querydefs with plain DDL CREATE VIEW foo AS ... syntax, in fact I'm not sure you can (?)

But here's a little piece of a script I wrote for backing up queries to separate .sql files (which is part of a larger script for backing up all front-end db code, see Oliver's answer for this question).

Dim oApplication
Set oApplication = CreateObject("Access.Application")
oApplication.OpenCurrentDatabase sMyAccessFilePath
oApplication.Visible = False

For Each myObj In oApplication.DBEngine(0)(0).QueryDefs
    writeToFile sExportpath & "\queries\" & myObj.Name & ".sql", myObj.SQL 
Next

Function writeToFile(path, text)
Dim fso, st
  Set fso = CreateObject("Scripting.FileSystemObject")
  Set st = fso.CreateTextFile(path, True)
  st.Write text
  st.Close
End Function
毁梦 2024-07-22 11:35:38

以下 C# 概述了如何从 .mdb 文件获取架构。

获取数据库连接:

String f = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + "database.mdb";
OleDbConnection databaseConnection = new OleDbConnection(f);
databaseConnection.Open();

获取每个表的名称:

DataTable dataTable = databaseConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });
int numTables = dataTable.Rows.Count;
for (int tableIndex = 0; tableIndex < numTables; ++tableIndex)
{
    String tableName = dataTable.Rows[tableIndex]["TABLE_NAME"].ToString();

获取每个表的字段:

    DataTable schemaTable = databaseConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new object[] { null, null, tableName, null });
    foreach (DataRow row in schemaTable.Rows)
    {
        String fieldName = row["COLUMN_NAME"].ToString(); //3
        String fieldType = row["DATA_TYPE"].ToString(); // 11
        String fieldDescription = row["DESCRIPTION"].ToString(); //27
    }
}

31127 在哪里来自? 我通过使用调试器检查 DataRow.ItemArray 找到了它们,有人知道“正确”的方法吗?


这是 ProVega 在此答案的评论中提到的屏幕截图:

数字列表,旁边有说明

The following C# outlines how to obtain the schema from a .mdb file.

Obtain a connection to the database:

String f = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + "database.mdb";
OleDbConnection databaseConnection = new OleDbConnection(f);
databaseConnection.Open();

Get the name of each table:

DataTable dataTable = databaseConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });
int numTables = dataTable.Rows.Count;
for (int tableIndex = 0; tableIndex < numTables; ++tableIndex)
{
    String tableName = dataTable.Rows[tableIndex]["TABLE_NAME"].ToString();

Get the fields for each table:

    DataTable schemaTable = databaseConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new object[] { null, null, tableName, null });
    foreach (DataRow row in schemaTable.Rows)
    {
        String fieldName = row["COLUMN_NAME"].ToString(); //3
        String fieldType = row["DATA_TYPE"].ToString(); // 11
        String fieldDescription = row["DESCRIPTION"].ToString(); //27
    }
}

Where do the 3, 11 and 27 come from? I found them by inspecting DataRow.ItemArray with a debugger, does anyone know the 'correct' way?


Here is the screenshot ProVega alludes to in the comments of this answer:

a list of numbers with descriptions next to them

-残月青衣踏尘吟 2024-07-22 11:35:38

如果您愿意使用纯 Access SQL 之外的其他内容,则可以保留 ADOX 对象的集合并使用它们来重新创建表结构。

示例(在 Python 中,当前不重新创建关系和索引,因为我正在处理的项目不需要它):

import os
import sys
import datetime
import comtypes.client as client

class Db:
    def __init__(self, original_con_string = None, file_path = None,
                 new_con_string = None, localise_links = False):
        self.original_con_string = original_con_string
        self.file_path = file_path
        self.new_con_string = new_con_string
        self.localise_links = localise_links

    def output_table_structures(self, verbosity = 0):
        if os.path.exists(self.file_path):
            if not os.path.isdir(self.file_path):
                raise Exception("file_path must be a directory!")
        else:
            os.mkdir(self.file_path)
        cat = client.CreateObject("ADOX.Catalog")
        cat.ActiveConnection = self.original_con_string
        linked_tables = ()
        for table in cat.Tables:
            if table.Type == u"TABLE":
                f = open(self.file_path + os.path.sep +
                         "Tablestruct_" + table.Name + ".txt", "w")
                conn = client.CreateObject("ADODB.Connection")
                conn.ConnectionString = self.original_con_string
                rs = client.CreateObject("ADODB.Recordset")
                conn.Open()
                rs.Open("SELECT TOP 1 * FROM [%s];" % table.Name, conn)
                for field in rs.Fields:
                    col = table.Columns[field.Name]
                    col_details = (col.Name, col.Type, col.DefinedSize,
                                   col.Attributes)
                    property_dict = {}
                    property_dict["Autoincrement"] = (
                        col.Properties["Autoincrement"].Value)
                    col_details += property_dict,
                    f.write(repr(col_details) + "\n")
                rs.Close()
                conn.Close()
                f.close()
            if table.Type == u"LINK":
                table_details = table.Name,
                table_details += table.Properties(
                    "Jet OLEDB:Link DataSource").Value,
                table_details += table.Properties(
                    "Jet OLEDB:Link Provider String").Value,
                table_details += table.Properties(
                    "Jet OLEDB:Remote Table Name").Value,
                linked_tables += table_details,
        if linked_tables != ():
            f = open(self.file_path + os.path.sep +
                     "linked_list.txt", "w")
            for t in linked_tables:
                f.write(repr(t) + "\n")
        cat.ActiveConnection.Close()

类似的反向函数使用第二个连接字符串重建数据库。

If you're happy to use something other than pure Access SQL, you could persist a collection of ADOX objects and use those to recreate the table structure.

Example (in Python, doesn't currently recreate relationships and indexes as it wasn't needed for the project I was working on):

import os
import sys
import datetime
import comtypes.client as client

class Db:
    def __init__(self, original_con_string = None, file_path = None,
                 new_con_string = None, localise_links = False):
        self.original_con_string = original_con_string
        self.file_path = file_path
        self.new_con_string = new_con_string
        self.localise_links = localise_links

    def output_table_structures(self, verbosity = 0):
        if os.path.exists(self.file_path):
            if not os.path.isdir(self.file_path):
                raise Exception("file_path must be a directory!")
        else:
            os.mkdir(self.file_path)
        cat = client.CreateObject("ADOX.Catalog")
        cat.ActiveConnection = self.original_con_string
        linked_tables = ()
        for table in cat.Tables:
            if table.Type == u"TABLE":
                f = open(self.file_path + os.path.sep +
                         "Tablestruct_" + table.Name + ".txt", "w")
                conn = client.CreateObject("ADODB.Connection")
                conn.ConnectionString = self.original_con_string
                rs = client.CreateObject("ADODB.Recordset")
                conn.Open()
                rs.Open("SELECT TOP 1 * FROM [%s];" % table.Name, conn)
                for field in rs.Fields:
                    col = table.Columns[field.Name]
                    col_details = (col.Name, col.Type, col.DefinedSize,
                                   col.Attributes)
                    property_dict = {}
                    property_dict["Autoincrement"] = (
                        col.Properties["Autoincrement"].Value)
                    col_details += property_dict,
                    f.write(repr(col_details) + "\n")
                rs.Close()
                conn.Close()
                f.close()
            if table.Type == u"LINK":
                table_details = table.Name,
                table_details += table.Properties(
                    "Jet OLEDB:Link DataSource").Value,
                table_details += table.Properties(
                    "Jet OLEDB:Link Provider String").Value,
                table_details += table.Properties(
                    "Jet OLEDB:Remote Table Name").Value,
                linked_tables += table_details,
        if linked_tables != ():
            f = open(self.file_path + os.path.sep +
                     "linked_list.txt", "w")
            for t in linked_tables:
                f.write(repr(t) + "\n")
        cat.ActiveConnection.Close()

A similar reverse function reconstructs the database using the second connection string.

独行侠 2024-07-22 11:35:38

您可以使用 ACE/Jet OLE DB 提供程序和 ADO Connection 对象的 OpenSchema 方法来获取作为 Recordset 的架构信息(这可能比 Collection 更好,因为它可以进行过滤、排序等)。

基本方法是使用 adSchemaTables 获取基表(不是 VIEW),然后使用每个 TABLE_NAME 获取 ORDINAL_POSITION、!DATA_TYPE、!IS_NULLABLE、!COLUMN_HASDEFAULT、!COLUMN_DEFAULT、!CHARACTER_MAXIMUM_LENGTH、!NUMERIC_PRECISION、!NUMERIC_SCALE 的 adSchemaColumns。

adSchemaPrimaryKeys 很简单。 adSchemaIndexes 是您可以找到 UNIQUE 约束的地方,不确定这些约束是否可以与唯一索引区分开,还有要插入 adSchemaForeignKeys 行集的外键名称,例如(伪代码):

rsFK.Filter = "FK_NAME = '" & !INDEX_NAME & "'") 

-- 注意 Jet 3.51 允许 FK 的陷阱基于无名 PK (!!)

验证规则和 CHECK 约束的名称可以在 adSchemaTableConstraints 行集中找到,使用 OpenSchema 调用中的表名称,然后使用调用 adSchemaCheckConstraints 行集中的名称,过滤 CONSTRAINT_TYPE = ' CHECK' (陷阱是名为 'ValidationRule' + Chr$(0) 的约束,因此最好转义名称中的空字符)。 请记住,ACE/Jet 验证规则可以是行级或表级(CHECK 约束始终是表级),因此您可能需要在过滤器中使用表名:对于 adSchemaTableConstraints 是 [].[].ValidationRule将是 adSchemaCheckConstraints 中的 [].ValidationRule。 另一个问题(疑似错误)是字段的宽度为 255 个字符,因此任何超过 255 个字符的验证规则/CHECK 约束定义都将具有 NULL 值。

adSchemaViews 用于基于非参数化 SELECT SQL DML 的访问查询对象,非常简单; 您可以使用 adSchemaColumns 中的 VIEW 名称来获取列详细信息。

PROCEDURES 位于 adSchemaProcedures 中,是所有其他类型的 Access Query 对象,包括参数化 SELECT DML; 对于后者,我更喜欢用 PROCEDURE_DEFINITION 中的 CREATE PROCEDURE PROCEDURE_NAME 替换 PARAMETERS 语法。 不要费心查看 adSchemaProcedureParameters,您将找不到任何内容:可以通过使用 ADOX Catalog 对象返回 ADO 命令来枚举参数,例如(伪代码):

Set Command = Catalog.Procedures(PROCEDURE_NAME).Command

然后枚举 .Name 的 Comm.Parameters 集合, .Type 表示 DATA_TYPE,(.Attributes 和 adParamNullable)表示 IS_NULLABLE,.Value 表示 COLUMN_HASDEFAULT 和 COLUMN_DEFAULT,.Size、.Precision、.NumericScale。

对于 ACE/Jet 特定的属性(例如 Unicode 压缩),您需要使用另一种对象。 例如,可以使用 ADO Catalog 对象找到 Access-speak 中的长整型自动编号,例如(伪代码):

bIsAutoincrement = Catalog.Tables(TABLE_NAME).Columns(COLUMN_NAME).Properties("Autoincrement").Value

祝你好运:)

You can use the ACE/Jet OLE DB Provider and an ADO Connection object's OpenSchema method to get schema information as a Recordset (which is arguable better than a Collection because it can be filtered, sorted, etc).

The basic methodology is to use adSchemaTables to get the base tables (not VIEWs), then use each TABLE_NAME to fetch adSchemaColumns for ORDINAL_POSITION, !DATA_TYPE, !IS_NULLABLE, !COLUMN_HASDEFAULT, !COLUMN_DEFAULT, !CHARACTER_MAXIMUM_LENGTH, !NUMERIC_PRECISION,!NUMERIC_SCALE.

adSchemaPrimaryKeys is straightforward. adSchemaIndexes is where you will find UNIQUE constraints, not sure wether these can be distinguished from unique indexes, also the names of FOREIGN KEYs to plug into the adSchemaForeignKeys rowset e.g. (pseudo code):

rsFK.Filter = "FK_NAME = '" & !INDEX_NAME & "'") 

-- watch for the gotcha that Jet 3.51 allows a FK based on a nameless PK (!!)

Names of Validation Rules and CHECK constraints can be found in the adSchemaTableConstraints rowset, using the table name in the OpenSchema call, then use the name in the call to the adSchemaCheckConstraints rowset, filter for CONSTRAINT_TYPE = 'CHECK' (a gotcha is a constraint named 'ValidationRule' + Chr$(0), so best to escape the null characters form the name). Remember that ACE/Jet Validation rules can be either row-level or table-level (CHECK constraints are always table-level), so you may need to use the table name in the filter: for adSchemaTableConstraints is [].[].ValidationRule will be [].ValidationRule in adSchemaCheckConstraints. Another gotcha (suspected bug) is that the Field is 255 characters wide, so any Validation Rule/CHECK constraint definition of more than 255 characters will have a NULL value.

adSchemaViews, for Access Query objects based on non-paramaterized SELECT SQL DML, is straightforward; you can use the VIEW name in adSchemaColumns to get the column details.

PROCEDURES are in adSchemaProcedures, being all other flavours of Access Query objects including parameterized SELECT DML; for the latter I prefer to replace the PARAMETERS syntax with CREATE PROCEDURE PROCEDURE_NAME in the PROCEDURE_DEFINITION. Don't boterh looking in the adSchemaProcedureParameters, you won't find anything: the parameters can be enumerated by using an ADOX Catalog object to return an ADO Command e.g. (pseudo code):

Set Command = Catalog.Procedures(PROCEDURE_NAME).Command

then enumerate the Comm.Parameters collection for the .Name, .Type for DATA_TYPE, (.Attributes And adParamNullable) for IS_NULLABLE, .Value for COLUMN_HASDEFAULT and COLUMN_DEFAULT, .Size, .Precision, .NumericScale.

For ACE/Jet-specific properties such as Unicode compression you need to use another kind of object. For example, a Long Integer Autonumber in Access-speak can be found using an ADO Catalog object e.g. (pseudo code):

bIsAutoincrement = Catalog.Tables(TABLE_NAME).Columns(COLUMN_NAME).Properties("Autoincrement").Value

Good luck :)

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