If mysql May 11, 2022 · 1、IF EXISTS（结果集)是指如果存在结果集（结果集的记录数大于0),就执行。就是说：EXISTS（结果集)是一个条件。是IF (条件)中“条件”的一种。 Summary: in this tutorial, you will learn how to use the MySQL OR operator to combine Boolean expressions. See syntax, parameters, examples and important points about this control flow function. A OR B Code language: SQL (Structured Query Language) (sql) Building upon the accepted answer, but only requiring one SELECT call (written for MySQL): delimiter $$ create procedure select_or_insert() begin SET @myId := (SELECT id FROM users WHERE username = 'something'); IF (ISNULL(@myId)) THEN INSERT INTO users (username) VALUES ('something'); END IF; end $$ Oct 10, 2023 · Summary: in this tutorial, you will learn about the MySQL SUM IF function to perform conditional summation. Note: MySQL 8. Open the MySQL command line client on your system. For example, the MySQL Version() function returns the current version of the MySQL database. For the preceding example, if t2 contains any rows, even rows with nothing but NULL values, the EXISTS condition is TRUE . Feb 22, 2017 · I want to write IF statement inside a Stored procedure in MySQL in the following way: IF (exp1 and exp2 and exp3) or exp4 I know MySQL will treat IF() as a function call. 9 Testing The MySQL Installation You can test whether the MySQL server is working by executing any of the following commands: MySQL - IF Statement - The IF is a compound MySQL statement which has a single or set of statements and a condition. 5; MySQL 5. ajuthphoqfxlxflykuijmfkllunotdopzkzggbgjrqwnuuslutsnfwtstmcacvmhktmekvrgkn