在表players 中执行 ‘select * from where leaguno =null’,结果一条记录都没查询出来!!'leaguno'字段的类型为‘CHAR’!!请问这样的写法是否正确!!!
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select * from tablename where leaguno is null
(PLAYERNO INTEGER NOT NULL,
NAME CHAR(15) NOT NULL,
INITIALS CHAR(3) NOT NULL,
BIRTH_DATE DATE ,
SEX CHAR(1) NOT NULL,
JOINED SMALLINT NOT NULL,
STREET VARCHAR(30) NOT NULL,
HOUSENO CHAR(4) ,
POSTCODE CHAR(6) ,
TOWN VARCHAR(30) NOT NULL,
PHONENO CHAR(13) ,
LEAGUENO CHAR(4) ,
PRIMARY KEY (PLAYNO) );
我都尝试了,还是不行!!!你看和我的表创建有关系没????
create table PLAYERS1 (
INITIALS varchar(10),
NAME varchar(20),
LEAGUENO char(4)
);insert into PLAYERS1 values
('R','Everentt','2411'),
('R','Parmentter','8467'),
('GWS','Wise',null),
('D','Bishop',null),
('M','Brown','6409'),
('PK','Hope','1608'),
('P','Parmenter','6524'); select * from PLAYERS1;select INITIALS,NAME , LEAGUENO,
CASE WHEN LEAGUENO IS NULL THEN '1' END AS NEW_LEAGUENO
FROM PLAYERS1;