![]() ![]() Moreover, we can also use CASE statements to compare conditions.Įxample: Consider a table named CONTACTS which contains contactID and a websiteID. The above procedure (function) takes a variable of varchar data type as its argument, and on that basis, sorts the tuples in the Student table. The output gets sorted according to the provided field. SELECT StudentID, Name, Gender, Department Sample QueryĬASE Switch in SQL- Custom Sorting Sample Query Since the values written in the Gender field are single character values (M/F), let us write a query to change M to Male and F to Female. The corresponding department names get renamed as follows: Student IDĮxample: Consider a scenario, where you have to select all the fields corresponding to the Student table. Sample Queryĭepartment='Electronics and Communication' If the dept name is CS, It should be converted to Computer Science L ikewise, Mech should be converted to Mechanical.a nd EC to Electronic and Communication. Let’s consider a table: STUDENT Student Table Student IDĮxample: Consider a scenario, where you have to modify the department names to their full forms. WHEN search_condition THEN statement_list Consider a search_condition instead of variable equality and execute the statement_list accordingly.Takes a variable called case_value and matches it with some statement_list.There can be two ways to achieve CASE-Switch statements: Syntax of CASE statement in MySQL Basic syntax: If there is no ELSE clause and none of the conditions are true, it simply returns NULL. If none of the conditions are true, it returns the value in the ELSE clause. Once a condition is true, it will stop traversing and return the result. The CASE statement goes through various conditions and returns values as and when the first condition is met (like an IF-THEN-ELSE statement in low-level languages). ![]() It is a kind of control statement which forms the cell of programming languages as they control the execution of other sets of statements. What is the CASE statement in MySQL?ĬASE statement in MySQL is a way of handling the if/else logic. We use SQL statements to perform tasks such as update, insert, delete or retrieve data from a database. According to ANSI (American National Standards Institute), it is considered as the standard language for relational database management systems (RDBMS). SQL is basically used to communicate with a database. I general, SQL is a standard language which helps to store, manipulate and retrieve data in databases. It is designed for managing data contained in a relational database management system(RDBMS), or for stream processing in a relational data stream management system. SQL is a domain-specific language which is extensively used in programming. The following topics will be covered in this article: In this article on the CASE statement in MySQL, I will discuss how to use this statement, to retrieve data on a single condition or multiple conditions. With a humongous amount of data getting generated every day, it is important to retrieve data based on a few conditions. ![]()
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