Search results
25 lut 2016 · The following query is not returning values for CurrentVisitor in my ms access 2010 database: SELECT ClientNumber, MAX(LastVisitDate) AS LastVisitStart. FROM VisitsTable. GROUP BY ClientNumber) AS t. I think the reason is that the check for null in the If() operation is not written correctly.
Definition and Usage. The NULLIF () function returns NULL if two expressions are equal, otherwise it returns the first expression. Syntax. NULLIF (expr1, expr2) Parameter Values. Technical Details. More Examples. Example. Compare two expressions: SELECT NULLIF('Hello', 'Hello'); Try it Yourself » Example. Compare two expressions:
NULLIF is equivalent to a searched CASE expression in which the two expressions are equal and the resulting expression is NULL. We recommend that you not use time-dependent functions, such as RAND(), within a NULLIF function.
SQL Server NULLIF expression overview. The NULLIF expression accepts two arguments and returns NULL if two arguments are equal. Otherwise, it returns the first expression. The following shows the syntax of the NULLIF expression: NULLIF(expression1, expression2) Code language: SQL (Structured Query Language) (sql)
15 sty 2021 · SQL NULLIF expression compares two expression and returns a null value if the two specified expressions are equal, else it returns the first expression. NULLIF expression is equivalent to a searched CASE expression in which the two expressions are equal and the resulting expression is NULL.
Syntax. The syntax for the NULLIF expression is as follows: NULLIF(expression1, expression2) The expression1 and expression2 are the two values or columns you want to compare. If expression1 and expression2 are equal, the NULLIF function returns a null value. Otherwise, it returns the value of expression1.
This SQL Server tutorial explains how to use the NULLIF function in SQL Server (Transact-SQL) with syntax and examples. In SQL Server (Transact-SQL), the NULLIF function compares expression1 and expression2.
