SQL&MySQL查询添加字段为行号_MySQL
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SQL&MySQL查询添加字段为行号
SQL:
select row_number() over(order by col desc) ,* from table;
函数“row_number”必须有使用 ORDER BY 的 OVER 子句,按照字段col来排
列自动取值
MySQL:
SET @r=0;
SELECT @r:=IFNULL(@r,0)+1 AS rownum,table.* FROM table ORDER BY col DESC;
与SQL不同,为循环添加字段,如果查询所有行必须加上表名table.*,若取某个
字段则不需要,col1,col2...
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