要部分转储 SQL Server 数据并限制每个表中转储的行数,可以使用以下解决方法之一:
方法1:使用 TOP 子句和 WHERE 子句
DECLARE @MaxRowsPerTable INT = 1000; -- 每个表转储的最大行数
DECLARE @TableName NVARCHAR(100);
DECLARE @RowCount INT;
DECLARE TableCursor CURSOR FOR
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'; -- 只选择基础表,不包括视图等
OPEN TableCursor;
FETCH NEXT FROM TableCursor INTO @TableName;
WHILE @@FETCH_STATUS = 0
BEGIN
SET @RowCount = 0;
WHILE @RowCount < @MaxRowsPerTable
BEGIN
-- 使用 TOP 子句限制每个表中转储的行数
EXEC('INSERT INTO YourDestinationTable SELECT TOP ' + CAST(@MaxRowsPerTable - @RowCount AS NVARCHAR(10)) + ' * FROM ' + @TableName);
SET @RowCount = @RowCount + @@ROWCOUNT;
IF @RowCount >= @MaxRowsPerTable
BREAK;
END
FETCH NEXT FROM TableCursor INTO @TableName;
END
CLOSE TableCursor;
DEALLOCATE TableCursor;
方法2:使用 OFFSET FETCH 子句
DECLARE @MaxRowsPerTable INT = 1000; -- 每个表转储的最大行数
DECLARE @TableName NVARCHAR(100);
DECLARE @RowCount INT;
DECLARE TableCursor CURSOR FOR
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'; -- 只选择基础表,不包括视图等
OPEN TableCursor;
FETCH NEXT FROM TableCursor INTO @TableName;
WHILE @@FETCH_STATUS = 0
BEGIN
SET @RowCount = 0;
DECLARE @Offset INT = 0;
WHILE @RowCount < @MaxRowsPerTable
BEGIN
-- 使用 OFFSET FETCH 子句限制每个表中转储的行数
EXEC('INSERT INTO YourDestinationTable SELECT * FROM ' + @TableName + ' ORDER BY YourPrimaryKeyColumn OFFSET ' + CAST(@Offset AS NVARCHAR(10)) + ' ROWS FETCH NEXT ' + CAST(@MaxRowsPerTable - @RowCount AS NVARCHAR(10)) + ' ROWS ONLY');
SET @RowCount = @RowCount + @@ROWCOUNT;
IF @RowCount >= @MaxRowsPerTable
BREAK;
SET @Offset = @Offset + @MaxRowsPerTable - @RowCount;
END
FETCH NEXT FROM TableCursor INTO @TableName;
END
CLOSE TableCursor;
DEALLOCATE TableCursor;
上述代码示例使用游标(CURSOR)遍历数据库中的每个基础表,并在每个表中使用 TOP 子句或 OFFSET FETCH 子句限制转储的行数。请将 YourDestinationTable
替换为目标表的名称,并根据需要调整每个表转储的最大行数(@MaxRowsPerTable
)。
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