The key to using simple CASE statements effectively is understanding how to compare an expression to fixed values.The expression in a simple CASE statement can be a column name, a function, or any valid SQL exp
If the result of a selector value equals the result of the selector, then the associated sequence of statements executes and the CASE statement ends. In addition, the subsequent selector values are not evaluated. 3) ELSE else_statements If no values in WHERE clauses match the result of ...
SELECTcolumn1, column2, ...CASEWHENcondition1THENresult1WHENcondition2THENresult2-- Add more WHEN conditions and results as neededENDASalias_nameFROMtable_name; We can add as manyWHEN ... THENconditions as required in theCASEstatement. For example, -- multiple CASE conditions in SQLSELECTcusto...
SELECT first_name, last_name FROM student_details; You can also use clauses like WHERE, GROUP BY, HAVING, ORDER BY with SELECT statement. We will discuss these commands in coming chapters. NOTE: In a SQL SELECT statement only SELECT and FROM statements are mandatory. Other clauses like ...
clause:子句,一条SQL里的部分,比如上面的SELECT xxx,JOIN xxx,HAVING xxx等都是。一条statement由若干条clause按一定顺序组成(语法规则)。 experession:表达式,clause中的一部分,比如 WHERE id>1 里的 id>1 是个expression 一些不常见的SQL语句: 不常见的一些SQL:SELECTCOALESCE(age,'42')FROMusers;SELECT*FROM...
报错:ERROR: Query:[xxx] Get result failed: canceling statement due to user request 问题原因:查询被取消,通常是因为表被执行了DROP或TRUNCATE操作。 解决方法:可以通过HoloWeb Query洞察排查是否有冲突的DDL,详情请参见Query洞察。后期尽量避免Query执行过程中有DDL冲突任务。
TheSELECTstatement is used to select data from a database. ExampleGet your own SQL Server Return data from the Customers table: SELECTCustomerName, CityFROMCustomers; Try it Yourself » Syntax SELECTcolumn1,column2, ... FROMtable_name; ...
lock_owner_type data NULL c--m Cursor 2 sqlserver lock_deadlock event o--c resource_type lock_resource_type data NULL c--m PAGE 6 Therefore, on your CREATE EVENT SESSION statement, in its ADD EVENT WHERE clause, you could put: WHERE( ... resource_type ...
The SQL SELECT statement is used to select data from a database table and the selected data is returned in the form of a table. Syntax The syntax for using SELECT statement in different scenarios are given below: /*select one column*/ SELECT column1 FROM table_name; /*select multiple ...
We can also use theSELECT INTOstatement to create a new table with the given structure (without copying the data). For that, we use theWHEREclause with a condition that returnsfalse. -- copy table structure onlySELECT*INTONewCustomersFROMCustomersWHEREfalse; ...