What is difference among Single, SingleOrDefault, First and FirstOrDefault?

123

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Tell us what is extractor?

867

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what is the principle of the single phase energy meter? and,what is the advantages and disadvantages of single phase energy meter?

4464

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can you explain the difference between readfile vs createreadstream in nodejs.

472

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hi friends i am first time using this site.i came to by some tcs personals that certifications r important for placements.i am financially average i am learning java from books.please tell is it enough if not which certification should i go for

1756

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What are the advantages of windows 7?

751

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How to install django ?

454

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Why are file extensions important?

915

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why we use sinosidal voltage / current instead of others in system?

2149

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I have a frame that contains headings. This frame is enclosed in side a repeating frame. However the headings are not displayed on all pages it is displayed only on the last page. Please let me know why is this happening. print object on = All pages base printing on = enclosing object

2924

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What are the automatic variables for macro? : sas-macro

1146

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How to create an About Box in Delphi or C++ Builder?

2440

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can you give me the solution of iiie

2300

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What is the difference between DSM and RDD?

285

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What are the pertinent COBOL commands?

3108

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