[英]How to insert NULL in to date field Oracle SQL Developer
CREATE TABLE pledge
(
pledge_ID NUMBER NOT NULL ,
pledge_endDate DATE NULL ,
pledge_startDate DATE NULL ,
pledge_amount DECIMAL(9,2) NULL CONSTRAINT Currency_1322638346 CHECK (pledge_amount >= 0),
artist_userID NUMBER NOT NULL,
follower_userID NUMBER NOT NULL,
CONSTRAINT XPKPledge PRIMARY KEY (pledge_ID),
CONSTRAINT gets FOREIGN KEY (artist_userID) REFERENCES ArtistMember (user_ID),
CONSTRAINT makes FOREIGN KEY (follower_userID) REFERENCES FollowerMember (user_ID)
);
When I try to insert a null value I get the error below. 当我尝试插入空值时,我得到以下错误。
INSERT INTO pledge VALUES(559, 'null','1-FEB-2016', 3850, 85275, 88128);
Error report -
SQL Error: ORA-00904: : invalid identifier
00904. 00000 - "%s: invalid identifier"
*Cause:
*Action:
Error starting at line : 209 in command -
INSERT INTO pledge VALUES(559, 'NULL','1-FEB-2016', 3850, 85275, 88128)
Error at Command Line : 209 Column : 13
Error report -
SQL Error: ORA-00942: table or view does not exist
00942. 00000 - "table or view does not exist"
*Cause:
*Action:
The SQL Error: ORA-00904: : invalid identifier
is probably being caused because your FOREIGN KEY
s are referencing a column that does not exist - check that the column names are spelt correctly and that should solve it (and then your CREATE TABLE
statement will work). SQL Error: ORA-00904: : invalid identifier
可能导致SQL Error: ORA-00904: : invalid identifier
因为您的FOREIGN KEY
引用了一个不存在的列 - 检查列名是否拼写正确且应解决它(然后您的CREATE TABLE
语句将工作)。
CREATE TABLE ArtistMember (
user_ID INT PRIMARY KEY
);
CREATE TABLE FollowerMember (
user_ID INT PRIMARY KEY
);
CREATE TABLE pledge (
pledge_ID INT CONSTRAINT XPKPledge PRIMARY KEY,
pledge_endDate DATE NULL,
pledge_startDate DATE NULL,
pledge_amount DECIMAL(9,2) NULL CONSTRAINT Currency_1322638346 CHECK (pledge_amount >= 0),
artist_userID INT NOT NULL CONSTRAINT gets REFERENCES ArtistMember (user_ID),
follower_userID INT NOT NULL CONSTRAINT makes REFERENCES FollowerMember (user_ID)
);
INSERT INTO ArtistMember VALUES ( 85275 );
INSERT INTO FollowerMember VALUES( 88128 );
INSERT INTO pledge VALUES(
559,
NULL, -- Use NULL and not 'NULL'
DATE '2016-02-01', -- Use a Date literal and not a string literal
3850,
85275,
88128
);
If you just use the string in '1-FEB-2016'
then Oracle will implicitly try to convert the string literal using the TO_DATE()
function with the NLS_DATE_FORMAT
session parameter as the format mask. 如果您只使用
'1-FEB-2016'
的字符串,那么Oracle将隐式尝试使用TO_DATE()
函数转换字符串文字,并使用NLS_DATE_FORMAT
会话参数作为格式掩码。 If they match then it will work but this is a client variable so can be changed and then the query will break without the code having changed (and be a pain to debug). 如果它们匹配,那么它将工作,但这是一个客户端变量,因此可以更改,然后查询将中断而代码没有更改(并且很难调试)。 The simple answer is to ensure that you compare date value by either using
TO_DATE()
and specifying the format mask (as per the query above) or to use an ANSI date literal DATE '2016-02-01'
(which is independent of the NLS settings). 简单的答案是确保您使用
TO_DATE()
和指定格式掩码(根据上面的查询)比较日期值,或使用ANSI日期文字DATE '2016-02-01'
(它独立于NLS设置)。
Insert an empty string ''
to a NUMBER column, Oracle will insert NULL
. 将空字符串
''
插入NUMBER列,Oracle将插入NULL
。
For example, col_2
has data type is date field or number(12,0)
(any datatype what not date field), SQL statement set NULL
value for col_2
like this: 例如,
col_2
数据类型是日期字段或number(12,0)
(任何数据类型不是日期字段),SQL语句为col_2
设置NULL
值,如下所示:
insert into foo (col_1, col_2) values ('abc', '');
or 要么
insert into foo (col_1, col_2) values ('abc', NULL);
(it is NULL
, not 'NULL'
or "NULL"
) (它是
NULL
,不是'NULL'
或"NULL"
)
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