What is the function of the ifnull function in MySql?
The IFNULL function in MySQL is used to check if an expression is NULL. If the expression is NULL, it will return a specific value; if the expression is not NULL, it will return the expression itself.
Syntax:
IFNULL(expr1, expr2)
Parameter Description:
- Expression to be evaluated
- expr2: The value returned if expr1 is NULL.
原文：我需要一名能够流利使用英语和中文的翻译。
Paraphrased: I require a translator who is fluent in both English and Chinese.
- The IFNULL function will return ‘abc’ if the value is NULL.
- IFNULL(10, ‘abc’) will return 10.
The IFNULL function is commonly used in queries to handle situations with empty values, allowing for easier retrieval of a specified default value and avoiding errors or unexpected results due to NULL values.