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What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?

...ered Aug 11 '12 at 14:34 umarali1981umarali1981 78177 silver badges99 bronze badges ...
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Sql Server string to date conversion

...tedDate, 100 as FormatValue, 'mon dd yyyy hh:miAM (or PM)' as OutputFormat union all select @d,convert(varchar,@d,101),101,'mm/dd/yy' union all select @d,convert(varchar,@d,102),102,'yy.mm.dd' union all select @d,convert(varchar,@d,103),103,'dd/mm/yy' union all select @d,convert(varchar,@d,104),104,...
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Difference between app.all('*') and app.use('/')

...wered Nov 13 '13 at 13:48 daemon1981daemon1981 18611 silver badge66 bronze badges ...
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How can mixed data types (int, float, char, etc) be stored in an array?

... You can make the array elements a discriminated union, aka tagged union. struct { enum { is_int, is_float, is_char } type; union { int ival; float fval; char cval; } val; } my_array[10]; The type member is used to hold the choice of w...
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Why is '+' not understood by Python sets?

...ts don't have an implementation for the + operator. You can use | for set union and & for set intersection. Sets do implement - as set difference. You can also use ^ for symmetric set difference (i.e., it will return a new set with only the objects that appear in one set but do not appear in b...
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How can I select from list of values in SQL Server

...a long list of comma delimited text would be to use a find an replace with UNION to get the distinct values. SELECT 1 UNION SELECT 1 UNION SELECT 1 UNION SELECT 2 UNION SELECT 5 UNION SELECT 1 UNION SELECT 6 Applied to your long line of comma delimited text Find and replace every comma with UNI...
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Difference between EXISTS and IN in SQL?

... t1Id INT, someData VARCHAR(20)) GO INSERT INTO t1 SELECT 1, 'title 1', 5 UNION ALL SELECT 2, 'title 2', 5 UNION ALL SELECT 3, 'title 3', 5 UNION ALL SELECT 4, 'title 4', 5 UNION ALL SELECT null, 'title 5', 5 UNION ALL SELECT null, 'title 6', 5 INSERT INTO t2 SELECT 1, 1, 'data 1' UNION ALL SELECT...
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What are Aggregates and PODs and how/why are they special?

...lass can also be an aggregate if… wait! nothing is said about structs or unions, can't they be aggregates? Yes, they can. In C++, the term class refers to all classes, structs, and unions. So, a class (or struct, or union) is an aggregate if and only if it satisfies the criteria from the above def...
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Is it possible to insert multiple rows at a time in an SQLite database?

...TO 'tablename' SELECT 'data1' AS 'column1', 'data2' AS 'column2' UNION ALL SELECT 'data1', 'data2' UNION ALL SELECT 'data1', 'data2' UNION ALL SELECT 'data1', 'data2' a note on performance I originally used this technique to efficiently load large datasets from Ruby on Rails. However, as...
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Union Vs Concat in Linq

I have a question on Union and Concat . I guess both are behaving same in case of List<T> . 3 Answers ...