MySql查询按星期几选择列

Question

我有以下表格结构

ID     IS_SUNDAY        IS_MONDAY         REST DAys..

11    Boolean value     Boolean value     Boolean value    

12    Boolean value     Boolean value     Boolean value

Answer 1

下一个查询将允许您选择当前星期几的列：

SELECT 
  CASE DAYOFWEEK(CURRENT_DATE)
    WHEN 1 THEN IS_SUNDAY
    WHEN 2 THEN IS_MONDAY
    WHEN 3 THEN IS_TUESDAY
    WHEN 4 THEN IS_WEDNESDAY
    WHEN 5 THEN IS_THURSDAY
    WHEN 6 THEN IS_FRIDAY
    WHEN 7 THEN IS_SATURDAY
  END CURRENT_DAY_OF_WEK
FROM DAYS_TABLE;  

Answer 2

SELECT IS_SUNDAY FROM yourTable WHERE ID = 11

但我建议你在问这么简单的问题之前先阅读一本好的教程或一本书。

Answer 3

您可以使用获取列名称

SELECT  COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE COLUMN_NAME like '%columnname%' AND TABLE_NAME='table_name';