访问嵌套游标中的变量的问题

Question

我从 sys 表中获取一组表名，并尝试遍历它们以从中获取列，然后附加到动态 SQL 中的字符串。

我遇到语法问题。请帮我。 我试图将 @tablename 传递给 select * 语句，但它不喜欢它。请帮帮我

                DECLARE @col [VARCHAR](100);
            DECLARE @TableCursor AS CURSOR;


            SET 
            @TableCursor = CURSOR FOR
               SELECT   st.TABLE_NAME
               FROM     INFORMATION_SCHEMA.TABLES st
               WHERE    REPLACE(st.TABLE_NAME, 'TEST' + '_' + 'PIV' + '_', '') = 'Marketing_campaign'
                        AND st.TABLE_SCHEMA = 'DV';
            DECLARE @Tablename VARCHAR(100);

            OPEN @TableCursor;
            FETCH NEXT FROM @TableCursor 
                INTO @Tablename;

            WHILE @@FETCH_STATUS = 0
                BEGIN
                    DECLARE @colCursor AS CURSOR;

                    SET @colCursor = CURSOR FOR
                        SELECT * FROM  @Tablename; ****** this is where its complaining****

                    OPEN @colCursor;
                    FETCH NEXT FROM @colCursor 
                        INTO @col;
                    WHILE @@FETCH_STATUS = 0
                        BEGIN
                            CLOSE @colCursor;
                            DEALLOCATE @colCursor;

                        END;
                    FETCH NEXT FROM @TableCursor
                    INTO @Tablename;
                END;

            CLOSE @TableCursor;
            DEALLOCATE @TableCursor;

Answer 1

您正在从@Tablename 中选择 但在@Tablename 的定义中它是 varchar(100) 您不能从 varchar 中选择

如果你想选择你需要从表中选择

看看这个，它可能会有所帮助 Table name as variable