查询表table_name中col_name（字符串类型）的值是数字的记录 SELECT col_name,CAST(col_name AS UNSIGNED INTEGER) AS val FROM table_name WHERE col_name=0 OR col_name0 HAVING CHAR_LENGTH(col_name)=CHAR_LENGTH(val);
查询表table_name中col_name（字符串类型）的值是数字的记录
SELECT col_name,CAST(col_name AS UNSIGNED INTEGER) AS val
FROM table_name
WHERE col_name="0" OR col_name>0
HAVING CHAR_LENGTH(col_name)=CHAR_LENGTH(val);
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