在MySQL中,您可以执行以下操作:INSERT IGNORE INTO Table2(Id, Name) SELECT Id, Name FROM Table1SQL Server是否有类似的东西? 0 0 0 ABOUTYOU 我使用IanC建议ignore Duplicates的唯一索引来解决类似问题,使用Option创建索引WITH IGNORE_DUP_KEYIn backward compatible syntax, WITH IGNORE_DUP_KEY is e...
(0.01 sec) mysql> insert 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 | +---+---...
you can use the DISTINCT keyword to remove duplicates from your results. For instance if you wanted to just return a unique list of employees’ titles you would use this SQL SELECT statement:
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 ...
If SELECT DISTINCT is specified, all duplicate rows are removed from the result set (one row is kept from each group of duplicates). SELECT ALL specifies the opposite: all rows are kept; that is the default. SELECT DISTINCT ON ( expression [, ...] ) keeps only the first row of each...
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 通过JDBC 使用 INSERT INTO SELECT 旁路导入数据。 使用Connection.setAutoCommit(xx) 接口,开启自动提交事...
To eliminate duplicates within the week, I am assuming that you want to useCOUNT(DISTINCT ...)in your code. Instead of grouping by all fields, I will use SELECT DISTINCT to accomplish this. Once you have the data, you have the option to either PIVOT it to fit your table or utilize ...
Records: 5 Duplicates: 0 Warnings: 0 mysql> select * from stu; +---+---+---+ | id | age | name | +---+---+---+ | 1 | 22 | 张三 | | 2 | 25 | 李四 | | 3 | 26 | 张学友 | | 4 | 32 | 刘德华 | | 5 |...
mysql> insert into test1values(1,'a'),(2,'b'),(3,'c');QueryOK,3rows affected (0.01sec)Records:3Duplicates:0Warnings:0mysql> select a,bfromtest1; +---+---+ | a | b | +---+---+ |1| a | |2| b | |3| c |
Removes all duplicate rows from theSELECTresult set so one row is kept from each group of duplicates. Retains only the first row in the set of rows that have the same result calculated on the given expression. DISTINCT ONexpression is explained with the same rule ofORDER BY. Unless you use...