致命例外原因：android.database.sqlite.sqliteException副本列

Question

在Firebase Crashlytics上重新发布此崩溃： android.database.sqlite.sqliteException 重复列名称：run_in_foreground（sqlite代码1 sqlite_error）：，当编译时：Alter Table Workspec添加列Run_in_foreground Integer noteger none default default 0（OS错误-11：再一次）

无法找到根本原因）无法找到根本原因这个问题。以下是在此处使用的stacktrace

Fatal Exception: android.database.sqlite.SQLiteException: duplicate column name: run_in_foreground (Sqlite code 1 SQLITE_ERROR): , while compiling: ALTER TABLE workspec ADD COLUMN `run_in_foreground` INTEGER NOT NULL DEFAULT 0, (OS error - 11:Try again)
   at android.database.sqlite.SQLiteConnection.nativePrepareStatement(SQLiteConnection.java)
   at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:948)
   at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:559)
   at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:603)
   at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:63)
   at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
   at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:2081)
   at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:2003)
   at androidx.sqlite.db.framework.FrameworkSQLiteDatabase.execSQL(FrameworkSQLiteDatabase.java:242)
   at androidx.work.impl.WorkDatabaseMigrations$6.migrate(WorkDatabaseMigrations.java:209)
   at androidx.room.RoomOpenHelper.onUpgrade(RoomOpenHelper.java:99)
   at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.onUpgrade(FrameworkSQLiteOpenHelper.java:177)
   at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:417)
   at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:313)
   at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.getWritableSupportDatabase(FrameworkSQLiteOpenHelper.java:145)
   at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper.getWritableDatabase(FrameworkSQLiteOpenHelper.java:106)
   at androidx.room.RoomDatabase.beginTransaction(RoomDatabase.java:352)
   at androidx.work.impl.utils.ForceStopRunnable.cleanUp(ForceStopRunnable.java:156)
   at androidx.work.impl.utils.ForceStopRunnable.run(ForceStopRunnable.java:87)
   at androidx.work.impl.utils.SerialExecutor$Task.run(SerialExecutor.java:91)
   at java.util.concurrent.ThreadPoolExecutor.processTask(ThreadPoolExecutor.java:1187)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1152)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
   at java.lang.Thread.run(Thread.java:784)

需要帮助，因为由于这个问题，应用程序发布被卡住了。

Answer 1

与sqlite不同，说如果不存在一列已经存在，则原因很可能是该列实际上已经存在。

作为启动器和临时度量，您可以查看表是否确实已经具有列。例如，您可以拥有：

    val migration1_2 = Migration(1,2) {
        /* Will extract the SQL (schema) of the workspec table and write it to the log */
        DatabaseUtils.dumpCursor(it.query("SELECT sql FROM sqlite_master WHERE type = 'table' AND name LIKE 'workspec'"))
        it.execSQL("ALTER TABLE workspec ADD COLUMN `run_in_foreground`INTEGER NOT NULL DEFAULT 0")
        DatabaseUtils.dumpCursor(it.query("SELECT sql FROM sqlite_master WHERE type = 'table' AND name LIKE 'workspec'"))

    }

• -SQLITE_MASTER基本上是模式， sql 列包含用于创建组件的SQL（例如，表，索引，触发，触发器，视图），类型是组件类型（因此仅对表格感兴趣）名称是组件的名称（仅对WorksPec表感兴趣）。

然后使用此功能将输出以下内容到日志中： -

2022-04-21 21:13:17.631 I/System.out: >>>>> Dumping cursor android.database.sqlite.SQLiteCursor@9c8df94
2022-04-21 21:13:17.631 I/System.out: 0 {
2022-04-21 21:13:17.631 I/System.out:    sql=CREATE TABLE `WorkSpec` (`workSpecId` INTEGER, `another` TEXT NOT NULL, PRIMARY KEY(`workSpecId`))
2022-04-21 21:13:17.631 I/System.out: }
2022-04-21 21:13:17.631 I/System.out: <<<<<



2022-04-21 21:13:17.633 I/System.out: >>>>> Dumping cursor android.database.sqlite.SQLiteCursor@f1e7a3d
2022-04-21 21:13:17.633 I/System.out: 0 {
2022-04-21 21:13:17.633 I/System.out:    sql=CREATE TABLE `WorkSpec` (`workSpecId` INTEGER, `another` TEXT NOT NULL, `run_in_foreground`INTEGER NOT NULL DEFAULT 0, PRIMARY KEY(`workSpecId`))
2022-04-21 21:13:17.633 I/System.out: }
2022-04-21 21:13:17.634 I/System.out: <<<<<

• 请注意，可以看到第一个调用没有run_in_foreground列。第二个确实是，显示如果列不存在，则可以更改表命令。

当然，您可以进一步进行此操作，并检查结果，以查看该列是否已经存在并跳过Alter（如果适合）。

关于实际原因，日志不足以确定这一点，您可能需要在版本更改之前提供@entity注释的类版本更改后。

例如上述： -

@Entity
data class WorkSpec(
    @PrimaryKey
    val workSpecId: Long? = null,
    val another: String,
    /* ADDED for Version 2*/

    @ColumnInfo(defaultValue = "0")
    val run_in_foreground: Int

)