-- select first_name and last_name columns from Customers tableSELECTfirst_name, last_nameFROMCustomers; Run Code Here, the SQL command selects thefirst_nameandlast_nameof all customers in theCustomerstable. Example: SQL SELECT SQL SELECT ALL To select all columns from a database table, we ...
SELECTDateFROM OpenDataSource( 'Microsoft.Jet.OLEDB.4.0', 'Data Source="c:\Book1.xls"; User ID=Admin;Password=;Extended properties=Excel 8.0')...Sheet1$ In this example: The Excel file must be accessible by the SQL server (can be UNC path). Dateis the column name. Sheet1is the shee...
The following example uses theMERGE UNIONquery hint. SQL USEAdventureWorks2022; GOSELECTBusinessEntityID, JobTitle, HireDate, VacationHours, SickLeaveHoursFROMHumanResources.EmployeeASe1UNIONSELECTBusinessEntityID, JobTitle, HireDate, VacationHours, SickLeaveHoursFROMHumanResources.EmployeeASe2OPTION(MERGEUNI...
SELECTCONCAT(LastName,', ',FirstName)ASfullnameFROMemployeesCode language:SQL (Structured Query Language)(sql) AnSQL aliasis used to format the output in this example. Summary Use theSELECTstatement to query data from a table. Specify one or more column names after the SELECT clause to which...
一、基本的查询语句 ①查询个别列 select <列名1>,<列名2>··· ——select子句 from <表名>;...
第一部分 SELECT basics 1.The example uses a WHERE clause to show the population of 'France'. Note that strings (pieces of text that are data) should be in 'single quotes'; Modify it to show the population of Germany SELECT population ...
select distinct 姓名 from student; 删除重复数据查询结果 二:指定查询条件 1.选取‘姓名’列里值为‘猴子’的行 select 姓名,学号 from student where 姓名='猴子'; 查询条件:姓名是猴子的姓名和学号查询结果 三:单行注释及多行注释 单行注释符与注释之间要留一个空格 ...
A simple SQL query to this database could be: SELECT ename FROM emp; SELECT is SQL keyword which tells DBMS to select some data. Ename is a column name, as shown is table above. FROM is again SQL keyword which tells DBMS the table name from where to fetch data. ...
(SELECT ProductModelID FROM Production.ProductModel WHERE Name = 'Long-sleeve logo jersey') ; GO The following example usesINin a correlated, or repeating, subquery. This is a query that depends on the outer query for its values. The query is executed repeatedly, one time for each row tha...
// Limit / range - Fetch first result in this example. Usually used for performance reasons as well. $query->range(0,1); // Remove duplicates - using distinct in Drupal db_select. $query->distinct(); // Functions - You can use sql functions using addExpression ($expression, $alias ...