General PostgreSQL CASE expression The following illustrates the general form of the CASE statement: CASE WHEN condition_1 THEN result_1 WHEN condition_2 THEN result_2 [WHEN ...] [ELSE else_result] END In this syntax, each condition (condition_1, condition_2…) is a boolean expression that...
After restoring the database, you can view the table in thepgAdmininterface which comes with the default installation of PostgreSQL. Upon running a simpleSELECTstatement, you get to know about the columns, their data-types and also the rows the table is containing - The table contains details...
What is the difference between a simple CASE statement and a searched CASE statement in PostgreSQL? The conditions they handle are where the primary differences reside. A CASE statement that is searched permits more complicated criteria in each WHEN clause, whereas a simple CASE statement compares ...
This article shows how to use theCASEstatement in PostgreSQL. Thecasestatement is similar to theif-elsein the general programming language. But in SQL, if you want to writeIF-ELSE, you might needPL/SQL. In PostgreSQL, there’s built-in functionality to use thecaseexpressions. ...
when>=70 and age <=100 then 2 else 9 end as "年龄" from user where mobile="53437569"; 1. 2. 3. 4. 5. 6. 7. 查询结果如下: 忽然看到一篇讲解也很不错的文章,附链接:https://codedefault.com/2018/mysql-database-if-in-select-statement-choose-output-value-based-on-column-values ...
为了避免再次重复表达式，只需从查询结果中选择即可。例如：
为了避免再次重复表达式，只需从查询结果中选择即可。例如：
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在SQL中,CASE WHEN语句用于实现条件判断和分支逻辑。如果你希望缩短一个CASE WHEN语句,可以考虑以下几点: 1. 使用简洁的条件表达式:CASE WHEN语句中的条件表达式可以使用更...
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