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

17

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What is active record (ar) in yii framework?

1

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i need some information about "ACCESS POINT CONTROL PROTOCOL" in MOBILE COMPUTING

2753

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If we want to upload data through DataLoader, what the changes to be done?

1

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I WANT HOW CALCULATE TO CABLE FOR WELDING PLANT ?

764

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Name 3 available jquery plugins that bootstrap has in their query plugin library.

16

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What is flatmap in java8?

3

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Did india use the special safeguard provisions available in the agreement on agriculture? Will developing countries have recourse to any emergency safeguard measures in the doha round?

45

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What's the difference between comparison done by equals method and == operator?

27

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Tell us the difference between managed and unmanaged code?

9

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"In a four-stroke diesel engine, In what engine exhaust valve will open?"

722

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suppose the network connection between a webserver and clustered i-server gets lost. What will happen? Will the report still run?

18

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What is the difference between React Native and React?

3

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1.what is mean by 8/20 micro sec waveshape

1107

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What is a Contract? Can you place multiple contracts for similar goods in SAP SRM Contract Management?

40

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