将临时表值写入 .csv 文件

Question

我们动态创建了一个临时表。我们希望将完整的表格放入 .csv 文件中。怎么办？

DEF VAR ttH AS HANDLE NO-UNDO.
ttH:CREATE-LIKE(hBuffer).
ttH:Temp-table-prepare("tmytable")

Answer 1

因为您动态创建了临时表，所以不能使用 EXPORT 语句（至少据我所知）。不过，您可以做的是首先动态输出表的字段名称，然后输出字段值。就像这样：

DEFINE VARIABLE hQuery  AS HANDLE NO-UNDO.
DEFINE VARIABLE ttH     AS HANDLE NO-UNDO.

/* Define a new output stream  */
DEFINE STREAM s1.
OUTPUT stream s1 to "myCSV.csv".

/* Create a query for the contents of your temp-table */
CREATE QUERY hQuery.
/* Important: we need to use the temp-tables default buffer handle, 
/* not the hBuffer handle to the original table! */
hQuery:SET-BUFFERS (ttH:DEFAULT-BUFFER-HANDLE).
/* Use the name you created before for the FOR EACH clause */
hQuery:QUERY-PREPARE("FOR EACH tmytable").
hQuery:QUERY-OPEN().
hQuery:GET-FIRST().

/* Write out the names of the fields as header in the first row */
DEFINE VARIABLE i AS INTEGER NO-UNDO.
DO i = 1 TO ttH:DEFAULT-BUFFER-HANDLE:NUM-FIELDS:
    PUT STREAM s1 UNFORMATTED ttH:DEFAULT-BUFFER-HANDLE:buffer-field(i):name + ",".
END.
PUT STREAM s1 UNFORMATTED SKIP.

/* Walk through the query and output each field seperately. */
REPEAT:  
    hQuery:GET-NEXT().  
    IF hQuery:QUERY-OFF-END THEN LEAVE.  

    DO i = 1 TO ttH:DEFAULT-BUFFER-HANDLE:NUM-FIELDS:
        PUT STREAM s1 UNFORMATTED ttH:DEFAULT-BUFFER-HANDLE:buffer-field(i):buffer-value ",".
    END.
    PUT STREAM s1 UNFORMATTED SKIP.
END.

OUTPUT stream s1 close.

请注意，这可能不适用于大量表条目！

Answer 2

请参阅进度知识库 P4410用于范围处理语法。您可能还需要在 QUERY-PREPARE 之前将 FORWARD-ONLY=TRUE 添加到查询中，以可能提高性能。