Mysql when then else end

The IF statement can have THEN , ELSE, and ELSEIF clauses, and it is terminated with END IF. If a given search_condition evaluates to true, the corresponding THEN or ELSEIF clause statement_list executes. For the first syntax, case_value is an expression.

This value is compared to the when_value expression in each WHEN clause until one of them is equal. IF and ELSE control structure. If and Else control structure works only inside of a procedure.

So, once a condition is true, it will stop reading and return the result. If no conditions are true, it will return the value in the ELSE clause. If there is no ELSE part and no conditions are true, it returns NULL.

There is no corresponding ELSEIF() function or END IF keyword. T-SQL How to end an IF-ELSE IF-ELSE block. Can you have if- then.

One more thing, You also need to use GROUP BY clause or else you will be returning only one record even if you have different records,. The IF- THEN statement allows you to execute a set of SQL statements based on a specified. MySQL simple IF- THEN statement.

Transact-SQL Syntax Conventions. Its syntax is as follows: The statements must end with a semicolon. SQL is specifically designed to work with relational databases. I have a subscription table that contains subscriptions for a user.

Each user could have multiple rows indicating their subscription history. Nested IF-THEN-ELSE-END IF. The THEN part and the ELSE part, if any, can contain one or more IF- THEN - ELSE - END IF statement in one of the three forms. That is, when you feel it is necessary, you can use as many IF- THEN - ELSE - END IF statements in the THEN part and the ELSE part as you want. The SQL Else If statement is very useful to check multiple conditions at once.

It is an extension to the If then Else (which we discussed in the earlier post). If Else statement will only execute the statements when the given condition is either true or False but in real worl we may have to check. Following is an example to demonstrate it. An IF- THEN statement can be followed by an optional ELSIF.

Learn how to use IF… THEN logic in SQL Server , which allows users to execute programmatic logic on values within a query in real-time. SQL also has decision making statements. CASE计算条件列表并返回多个可能结果表达式之一. What I want is to check whether the column prefix exists and then remove it. However, I keep getting syntax errors, although this is what I found on stackoverflow.

I have tested with this sql statement and in all cases I have the correct. Mysql 学习记录 ( xampp 的 mysql 与 直接用 dnf 安装的 mysql 有冲突! ) 1. I use this code to show the full et or a part of it through a (IN) parameter in the stored procedure. Summary: in this tutorial, you will learn SQL Server IF.

Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party. ELSE statement to control the flow of program. If you have a little idea about how if.

END combination is like the if. TRUE executes its block of code. IF THEN ELSE , not working, but why? END em Funções e Procedimentos Armazenados - - Duration: 10:04.

Edit the SQL Statement, and click Run SQL to see the result. All the examples for this lesson are based on Microsoft.