sql - mysql，遍历列名

Question

我想从 MySQL 表中获取所有列名，遍历每个列名，然后使用这些列名作为变量运行存储过程。大意是:

colnames = get column names from table

for each colname
  if something changed then
    do something
  else
    do something else

看起来 SHOW COLUMNS FROM myTable 会给我列名，但是如何将列名放入循环中？

我真的很想使用原生 SQL 在存储过程中运行所有这些。因为我还在学习 MySQL 的复杂性，这对我的项目很有帮助。感谢您的帮助。

Answer 1

我想你想要这样的东西:

DECLARE col_names CURSOR FOR
  SELECT column_name
  FROM INFORMATION_SCHEMA.COLUMNS
  WHERE table_name = 'tbl_name'
  ORDER BY ordinal_position;


select FOUND_ROWS() into num_rows;

SET i = 1;
the_loop: LOOP

   IF i > num_rows THEN
        CLOSE col_names;
        LEAVE the_loop;
    END IF;


    FETCH col_names 
    INTO col_name;     

     //do whatever else you need to do with the col name

    SET i = i + 1;  
END LOOP the_loop;