into test1 values(1,'a'),(2,'b'),(3,'c'); Query OK, 3 rows affected (0.01 sec) Records: 3 Duplicates: 0 Warnings: 0 mysql> select a,b from test1; +---+---+ | a | b | +---+---+ | 1 | a | | 2 | b | | 3 | c | +---+---+ 3 rows in set (0.00 ...
obclient [SYS]> INSERT /*+ append enable_parallel_dml parallel(4) */ INTO test2 SELECT * FROM test; Query OK, 1000007 rows affected (8.683 sec) Records: 1000007 Duplicates: 0 Warnings: 0 c. 若设置 AUTOCOMMIT 为OFF 时旁路导入数据。 设置AUTOCOMMIT 为OFF。 obclient [SYS]> SET AUTOCOMMIT...
@文心快码BaiduComatesql select without duplicates multiple columns 文心快码BaiduComate 在SQL查询中,去除多列数据中的重复行,可以使用DISTINCT关键字。DISTINCT关键字用于确保查询结果中的每一行都是唯一的,适用于选择多列数据时的去重需求。下面我将详细解释如何使用DISTINCT关键字来去除多列数据中的重复行,并提供一个...
Records: 3 Duplicates: 0 Warnings: 0mysql> select * from test5; +---+---+---+ | a | b | c | +---+---+---+ | 1 | 2 | a | | 3 | NULL | b | | 4 | 5 | NULL | +---+---+---+ 3 rows in set (0.00 sec) 上⾯我们创建了⼀个表test5,3个字段,a不能为...
This command will return each country only once, regardless of how many times it appears in theCustomerstable. Example: SELECT -- select all countries from the Customers tableSELECTcountryFROMCustomers; This SQL command will return all country entries, including duplicates, from theCustomerstable. ...
2 rows in set (0.04 sec) mysql> insert into test1 values(1,'a'),(2,'b'),(3,'c'); Query OK, 3 rows affected (0.03 sec) Records: 3 Duplicates: 0 Warnings: 0 mysql> select * from test1; +---+---+ | a | b |
in 查询举一个例子来演示:mysql> create table test11(id int,age smallint); Query OK, 0 rows affected (0.01 sec) mysql> insert into test11 values(1,14),(2,15),(3,18),(4,20),(5,28),(6,10),(7,10),(8,30); Query OK, 8 rows affected (0.00 sec) Records: 8 Duplicates: 0...
Using DISTINCT on all columns of a table ensures that only completely unique rows, without any duplicates, are included in the result set. 6.Can we filter the results when using DISTINCT on multiple columns? Yes, we can filter the results using a WHERE clause in conjunction with DISTINCT to...
mysql>source/root/school.sql Database changed Query OK,0rowsaffected (0.02sec) Query OK,0rowsaffected (0.01sec) Query OK,0rowsaffected (0.01sec) Query OK,0rowsaffected (0.00sec) Query OK,10rowsaffected (0.03sec) Records:10Duplicates:0Warnings:0Query OK,4rowsaffected (0.00sec) ...
This example doesn't remove the duplicates between the two sets of five rows. The final result has 10 rows. SQL Copy USE AdventureWorks2022; GO IF OBJECT_ID('dbo.EmployeeOne', 'U') IS NOT NULL DROP TABLE dbo.EmployeeOne; GO IF OBJECT_ID('dbo.EmployeeTwo', 'U') IS NOT NULL ...