MYSQL 如何声明一个日期时间变量？
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时间：2020-08-31 16:15:09 来源:igfitidea点击:
MYSQL how to declare a datetime variable?
提问by u1230329
My code:
我的代码：
DECLARE report_date DATETIME;
set report_date='2013-01-17 00:00:00';
SELECT *
FROM `NMPP`.`capacitypersecond`
WHERE `StreamDT` >=report_date and `StreamDT` < '2013-01-18 00:00:00' ;
SELECT *
FROM `NMPP`.`capacityperHr`
WHERE `StreamDT` >=report_date and `StreamDT` < '2013-01-18 00:00:00' ;
SELECT *
FROM `NMPP`.`capacityperDay`
WHERE `TJLDate` >=report_date and `TJLDate` < '2013-01-18 00:00:00' ;
-
——
DECLARE report_date DATETIME;
/* SQL Error (1064): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DECLARE report_date DATETIME' at line 1 */
/* Affected rows: 0 Found rows: 0 Warnings: 0 Duration for 0 of 5 queries: 0.000 sec. */
采纳答案by palindrom
get rid of declare:
摆脱declare：
set @report_date = '2013-01-17 00:00:00';
SELECT *
FROM `NMPP`.`capacitypersecond`
WHERE `StreamDT` >= @report_date and `StreamDT` < '2013-01-18 00:00:00' ;
回答by spacepille
or with cast:
或与演员：
set @report_date = cast('2013-01-17 00:00:00' as datetime);
回答by Pazhani Samy
All the DECLARE should be at the start of the trigger,stored procedure.
所有的 DECLARE 都应该在触发器、存储过程的开始处。
This is not a C++ like language where you can mix declarations and statements, but more like C, where all declarations must be done before all statements.
这不是像 C++ 那样可以混合声明和语句的语言，而是更像 C，所有声明必须在所有语句之前完成。
