常用SQL总结

1.判断表是否存在,表内是否有数据

        SELECT
            table_name
        FROM
            information_schema.tables
        WHERE
            table_schema = #{database}
        AND table_name = #{tableName} AND TABLE_TYPE = 'BASE TABLE' AND TABLE_ROWS != 0;

2.如果主键不存在则插入数据，若存在则更新数据

        insert into
            bitools.account_retention(log_date, day_${day})
        values    
            (#{table_date},#{player_num})
        on duplicate key update
            day_${day} = #{player_num}

3.若主键重复，忽略插入 insert ignore into

4.若主键重复，替换插入 replace into