column BETWEEN A AND B
イコールA <=column and column <=B
なので、以下のSQLの結果は同一かと思ったが、一部の条件で挙動が異なった。
# andの後ろの項を含んでほしいのですが、含んでいない様子。 mysql> select '2010-07-26 00:00:00' BETWEEN '2010-07-25' AND '2010-07-26'; +-------------------------------------------------------------+ | '2010-07-26 00:00:00' BETWEEN '2010-07-25' AND '2010-07-26' | +-------------------------------------------------------------+ | 0 | +-------------------------------------------------------------+ 1 row in set (0.00 sec) # castをすれば含んでくれる mysql> select cast('2010-07-26 00:00:00' as datetime) BETWEEN '2010-07-25' AND '2010-07-26 00:00:00'; +----------------------------------------------------------------------------------------+ | cast('2010-07-26 00:00:00' as datetime) BETWEEN '2010-07-25' AND '2010-07-26 00:00:00' | +----------------------------------------------------------------------------------------+ | 1 | +----------------------------------------------------------------------------------------+ 1 row in set (0.01 sec)
なぜかというと、ただのクウォートだと文字として比較してしまうから。
比較対象のカラムは型を意識しなければならない。
mysql> SELECT CAST('2010-07-26 00:00:00' AS DATETIME) BETWEEN '2010-07-25' AND '2010-07-26'; +-------------------------------------------------------------------------------+ | CAST('2010-07-26 00:00:00' AS DATETIME) BETWEEN '2010-07-25' AND '2010-07-26' | +-------------------------------------------------------------------------------+ | 1 | +-------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
range指定は対象カラムの型に自動変換されるみたい。
DateとDatetimeの比較演算
mysql> SELECT @@global.time_zone, @@session.time_zone; +--------------------+---------------------+ | @@global.time_zone | @@session.time_zone | +--------------------+---------------------+ | UTC | UTC | +--------------------+---------------------+ 1 row in set (0.00 sec) mysql> mysql> mysql> mysql> select CAST('2014-08-04 13:00:00' AS DATETIME) <= '2014-08-04'; +---------------------------------------------------------+ | CAST('2014-08-04 13:00:00' AS DATETIME) <= '2014-08-04' | +---------------------------------------------------------+ | 0 | +---------------------------------------------------------+ 1 row in set (0.00 sec) mysql> select CAST('2014-08-05 00:00:00' AS DATETIME) <= '2014-08-04'; +---------------------------------------------------------+ | CAST('2014-08-04 10:00:00' AS DATETIME) <= '2014-08-04' | +---------------------------------------------------------+ | 0 | +---------------------------------------------------------+ 1 row in set (0.00 sec) mysql> select CAST('2014-08-04 00:00:00' AS DATETIME) <= '2014-08-04'; +---------------------------------------------------------+ | CAST('2014-08-04 00:00:00' AS DATETIME) <= '2014-08-04' | +---------------------------------------------------------+ | 1 | +---------------------------------------------------------+ 1 row in set (0.00 sec) mysql> select CAST('2014-08-04 00:00:01' AS DATETIME) <= '2014-08-04'; +---------------------------------------------------------+ | CAST('2014-08-04 00:00:01' AS DATETIME) <= '2014-08-04' | +---------------------------------------------------------+ | 0 | +---------------------------------------------------------+ 1 row in set (0.00 sec)
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