11/12/2023 0 Comments Mysql case slow![]() Now for Search CASE, it follows the same logical procedure as Simple CASE, but one part of the search case makes it different. You should not use NULL in the WHEN clause value because if executed, the logical part will be NULL = NULL which is FALSE. But if no value is equal, it returns the ELSE part value if provided. In the Simple CASE, the CASE the column value is matched with the conditional statement value in the WHEN clauses for equivalence and then produces the result value after that one in the syntax. Here, we have fetched the names of students, states, and cities where the CASE is applied with the ORDER BY clause to sort the result rows. If the case statement is not valid or the value is not found, then part value, i.e., State column value, is returned. ![]() In the above illustration, we have put the CASE statement on columns State and City, where if the State column contains a NULL value, then the query displays the City column value. Suppose the following query explains the CASE logical part where we have mentioned a table like Students with fields StudentName, State, City then the query will be written as: SELECT StudentName, State, City FROM Students ORDER BY (įrom here, we will come to know that when we have applied the CASE statement in the SELECT query to fetch the particular value that satisfies a specific case condition. We use a CASE statement to provide the result values based on a matched condition using the logical control method to the SQL queries and the SQL clauses like SELECT, WHERE, and ORDER BY. The CASE Statement contains two procedures: one is Simple CASE, and the other one is Searched CASE. You can evaluate through the syntax shown below: SELECT column1,column2,įROM TableName How Does CASE Statement Work in MySQL? We use the CASE statement anywhere with the clauses such as WHERE SELECT and ORDER BY to make a valid statement. This part allows adding logical CASE statements in a query in MySQL. Value: Denotes the value to be displayed when the else part is meeting.Value1, value2, ….,valueN: Represents the values required to display when a condition is met.Cond1,cond2,….,condN: Denotes the required conditions to be evaluated in the list of CASE statements.
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