For example, SELECT NULLIF(4,4) AS Same, NULLIF(5,7) AS Different; returns NULL for the first column (4 and 4) because the two input values are the same. The second column returns the first value (5) because the two input values are different.Transact-SQL syntax conventions...
nullif() has two parameters. The first one, is a variable, and the second one is a real number. We want a result that when param1 equals to param2, the function will return null. Normally this is helpful when we dodividecalculation. We can use nullif() to avoidthe “divided by zero...
COALESCE():返回第一个非NULL值。 NULLIF():若两个参数相等,则返回NULL。 示例代码 让我们来看看如何使用这些函数进行NULL值判断和处理。 -- 创建一个示例表CREATETABLEExampleTable(IDINTPRIMARYKEY,Name NVARCHAR(50),AgeINTNULL);-- 插入数据,包括NULL值INSERTINTOExampleTable(ID,Name,Age)VALUES(1,'Alice',...
Returns a null value if the two specified expressions are equal. For example,SELECT NULLIF(4,4) AS Same, NULLIF(5,7) AS Different;returns NULL for the first column (4 and 4) because the two input values are the same. The second column returns the first value (5) because the two inp...
For example, SELECT NULLIF(4,4) AS Same, NULLIF(5,7) AS Different; returns NULL for the first column (4 and 4) because the two input values are the same. The second column returns the first value (5) because the two input values are different. Transact-SQL syntax conventions Syntax ...
select nullif(10,20) from dual; 比较复杂的sql语句,可以使用case与decode 34、 case表达式 Case国际sql通用支持的,使用case可移植更好。 相当于在SQL中执行if语句 CASE 可用于允许使用有效表达式的任意语句或子句。 例如,可以在 SELECT、UPDATE、DELETE 和 SET 等语句以及 select_list、IN、WHERE、ORDER BY 和 ...
nullif--table level nullif clauseforexpress mode load field_names--field names settingforfirst recordofdata filesforexpress mode load dnfs_enable--optionforenabling or disabling DirectNFS(dNFS)forinput datafiles(DefaultFALSE)dnfs_readbuffers--the numberofDirectNFS(dNFS)readbuffers(Default4)sdf_pref...
Example Compare two expressions: SELECT NULLIF('Hello', 'Hello'); Try it Yourself » Example Compare two expressions: SELECT NULLIF('Hello', 'world'); Try it Yourself » Example Compare two expressions: SELECT NULLIF('2017-08-25', '2017-08-25'); Try it Yourself » ...
For example, SELECT NULLIF(4,4) AS Same, NULLIF(5,7) AS Different; returns NULL for the first column (4 and 4) because the two input values are the same. The second column returns the first value (5) because the two input values are different.Transact-SQL syntax conventions...
SQL_SVE_NULLIF (Intermediate level) SQL_STANDARD_CLI_CONFORMANCE 3.0 An SQLUINTEGER bitmask enumerating the CLI standard or standards to which the driver conforms. The following bitmasks are used to determine which levels the driver complies with:SQL_SCC_XOPEN_CLI_VERSION1: The driver complies ...