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Max or Default?

...d, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this: Dim x = (From y In context.MyTable _ Where y.MyField = value _ Select CType(y.MyCounter, Integer?)).Max Or in C#: var x = (from y...
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Effect of NOLOCK hint in SELECT statements

... 1) Yes, a select with NOLOCK will complete faster than a normal select. 2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select. Why would this be? NOLOCK typically (...
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Select distinct using linq [duplicate]

... myList.GroupBy(test => test.id) .Select(grp => grp.First()); Edit: as getting this IEnumerable<> into a List<> seems to be a mystery to many people, you can simply write: var result = myList.GroupBy(test => test.id) .S...
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NULL values inside NOT IN clause

... Query A is the same as: select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null Since 3 = 3 is true, you get a result. Query B is the same as: select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null When ansi_nulls is on, 3 <&...
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MySQL Data - Best way to implement paging?

...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements). With two arguments, the first argument specifies the offset of the first ro...
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Selecting a row of pandas series/dataframe by integer index

... The primary purpose of the DataFrame indexing operator, [] is to select columns. When the indexing operator is passed a string or integer, it attempts to find a column with that particular name and return it as a Series. So, in the question above: df[2] searches for a column name matchin...
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Invalid postback or callback argument. Event validation is enabled using '

... I had an experience with DataGrid. One of it's columns was "Select" button. When I was clicking "Select" button of any row I had received this error message: "Invalid postback or callback argument. Event validation is enabled using in configuration or <%@ Page EnableEve...
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html select option separator

How do you make a separator in a select tag? 14 Answers 14 ...
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How to count instances of character in SQL Column

... In SQL Server: SELECT LEN(REPLACE(myColumn, 'N', '')) FROM ... share | improve this answer | follow ...
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Find closing HTML tag in Sublime Text

...trl+Shift+A for Windows and Linux users, Command+Shift+A for Mac users) to select the whole block within the currently selected tag. For example, if you pressed this while your text cursor was within the outer div tag in the code below, all the divs with class selected would be selected. <div c...