Why is there a performance difference between two similar queries where one uses union and the other uses union all?

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How do I find the sql server instance name?

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What is the difference between ddl and dml?

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What are the types of processing and explain each? : sql server analysis services, ssas

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What is the difference between ‘having’ clause and a ‘where’ clause?

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What is tcl in sql server?

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Is BCNF better than 2NF & 3NF? Why?

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CREATE TABLE [dbo].[HPMS_CompetencyTypes](CompetencyType varchar(50) ) go create trigger hpms_create_Insert on HPMS_CompetencyTypes for insert as if Exists ( select * from [HPMS_CompetencyTypes] where CompetencyType=(select * from [HPMS_CompetencyTypes])) begin Rollback tran Raiserror ('duplicate value',12,6) go insert HPMS_CompetencyTypes (CompetencyType) values ('new') I'm new to trigger can any one tell me where is the issue. Please.

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Why are views required in the sql server or in any other database?

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What is difference between inner join and full join?

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How do you test your database? : sql server database administration

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Can we install sql server 2016 on windows 7?

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