What does <> (angle brackets) mean in MS-SQL Server?
Nov 8, 2013 · <> operator means not equal to in MS SQL. It compares two expressions (a comparison operator). When you compare nonnull expressions, the result is TRUE if the left …
sql - Not equal <> != operator on NULL - Stack Overflow
Oct 9, 2014 · <> is Standard SQL-92; != is its equivalent. Both evaluate for values, which NULL is not -- NULL is a placeholder to say there is the absence of a value. Which is why you can only …
What does the "@" symbol do in SQL? - Stack Overflow
Jul 30, 2012 · The @CustID means it's a parameter that you will supply a value for later in your code. This is the best way of protecting against SQL injection. Create your query using …
Should I use != or <> for not equal in T-SQL? - Stack Overflow
Apr 6, 2009 · Yes; Microsoft themselves recommend using <> over != specifically for ANSI compliance, e.g. in Microsoft Press training kit for 70-461 exam, "Querying Microsoft SQL …
sql - NOT IN vs NOT EXISTS - Stack Overflow
May 18, 2007 · In order to filter the student records that have a 10 grade in Math, we can use the EXISTS SQL operator, like this: SELECT id, first_name, last_name FROM student WHERE …
sql是什么，通俗的说，太专业听不懂？ - 知乎
sql是一门语言，就和我们平时说话一样，有主谓宾的层次结构，同样sql也有自己的一套语法规则。 记住这些语法规则就可以与数据库打交道了，不管是查询，新增，更新，删除数据，都可 …
SQL WITH clause example - Stack Overflow
Sep 23, 2012 · The SQL WITH clause was introduced by Oracle in the Oracle 9i release 2 database. The SQL WITH clause allows you to give a sub-query block a name (a process also …
How do I perform an IF...THEN in an SQL SELECT?
Sep 15, 2008 · The CASE expression cannot be used to control the flow of execution of Transact-SQL statements, statement blocks, user-defined functions, and stored procedures. If your …
sql - How do I split a delimited string so I can access individual ...
Nov 2, 2015 · SQL Server 2022 supports the following signature of STRING_SPLIT: STRING_SPLIT ( string , separator [ , enable_ordinal ] ) When enable_ordinal flag is set to 1 …
sql - What is SELF JOIN and when would you use it? - Stack Overflow
Jun 13, 2024 · You use a self join when a table references data in itself. E.g., an Employee table may have a SupervisorID column that points to the employee that is the boss of the current …