关于SELECT CASE语句的应用场景,它常用于需要根据不同条件返回不同结果的查询操作,例如根据不同的用户类型返回不同的权限,或者根据不同的商品状态返回不同的提示信息等。 腾讯云相关产品中,适合使用SELECT CASE语句的是腾讯云数据库 PostgreSQL 版,它是一种高度可扩展的关系型数据库产品,提供丰富的功能和灵活的查询语法。
Conditional statements are the core concepts in any programming paradigm. These statements include if, if-else, case, etc. TheCASEstatement is one of the conditional expressions that is used to create conditional queries. PostgreSQL allows us to use the WHEN-THEN case, if-else statements, etc. ...
Postgresql SELECT LEFT JOIN with case上的列 PostgreSQL是一种开源的关系型数据库管理系统,支持广泛的SQL语法和功能。在PostgreSQL中,SELECT语句用于从一个或多个表中检索数据。LEFT JOIN是一种连接操作,它返回左表中的所有行,以及与右表匹配的行。 在SELECT语句中使用LEFT JOIN和CASE语句可以根据条件将列的值进...
The PostgreSQL CASE expression is the same as IF/ELSE statement in other programming languages. It allows you to add if-else logic to the query to form a powerful query. Since CASE is an expression, you can use it in any place where you would use an expression such as SELECT, WHERE, ...
sql postgresql 我想运行下面的语句,但它给了我下面的错误 select case SEA.CONTENT_RESPONSE_STATE_ID when null then C.DISPLAY_NAME when 58 then 'Task Submission' when 59 then 'Sender Approved' end AS ACTION from table sea join table1 c 我有以下错误 错误:运算符不唯一:numeric=boolean提示:无法...
sql postgresql function 我正试着做这样的事情。正确的方法是什么 CREATE OR REPLACE function func(age bigint) RETURNS TABLE(years int, category text) AS $$ SELECT CASE WHEN age > 30 THEN SELECT CASE WHEN (age >= 60) THEN 0 WHEN (age >= 50) THEN 10 WHEN (age >= 40) THEN 20 ELSE...
For example,let’s suppose we want to categorize students based on their GPA as mentioned earlier. For this, we can use a searched CASE statement: SELECTname,CASEWHENgpa>=3.5THEN'Honors'WHENgpa>=2.5THEN'Satisfactory'ELSE'Needs Improvement'ENDASperformanceFROMStudent;+---+---+|name|performance...
Example 1: Basic Usage in a SELECT Statement Code: -- Select employees and categorize their salaries SELECT employee_name, salary, CASE WHEN salary > 70000 THEN 'High' WHEN salary BETWEEN 50000 AND 70000 THEN 'Medium' ELSE 'Low' END AS salary_category ...
CASE selector WHEN selector_value_1 THEN statements_1 WHEN selector_value_1 THEN statement_2 ... ELSE else_statements END CASE; Code language: PostgreSQL SQL dialect and PL/pgSQL (pgsql) Let’s examine the syntax of the simple CASE statement in detail: 1) selector The selector is an...
I want to perform a WHERE NOT EXISTS statement for a particular id. # Source data: MySQL curr_msql.execute(''' SELECT code, subjectname FROM test_subj ''') # Target data: PostgreSQL for row in curr_msql: curr_psql.execute(''' INSERT INTO subs ( created, modified, subjcode, subj...