Question

在MySQL程序中，我想要从一个动态查询创建的临时表计数行，即

CREATE TEMPORARY TABLE IF NOT EXISTS tmp_Tbl as select * from  dynamic_tbl;

描述临时tmp_Tbl; 说Field有15行，所以保存到会话变量@TotCols

再次从动态查询创建临时表：描述临时tmp_Tbl; 说Field有4行，所以保存到会话变量@TotCols

Answer 1

在存储例程的正文中，请尝试：

SET @create_tmp_table_sql = CONCAT(
    'CREATE TEMPORARY TABLE IF NOT EXISTS tmp_tbl AS ',
    'SELECT * FROM dynamic_tbl'
);
PREPARE create_tmp_table_stmt FROM @create_tmp_table_sql;
EXECUTE create_tmp_table_stmt;
DEALLOCATE PREPARE create_tmp_table_stmt;

SET @TotCols = (SELECT Count(*) FROM tmp_tbl);

MySQL计数临时表的显示列名称的总行数

1 个答案: