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Rails select helper - Default selected value, how?

... This should do it: <%= f.select :project_id, @project_select, :selected => params[:pid] %> share | improve this answer | ...
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MPICH vs OpenMPI

...make it the preferred implementation in nearly all cases. Feature Support from the Latest MPI Standard An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation of every single release of ...
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How to select a single field for all documents in a MongoDB collection?

...nt such as: db.student.find({}, {roll:1, _id:0}) The above statement will select all documents in the students collection, and the returned document will return only the roll field (and exclude the _id). If we don't mention _id:0 the fields returned will be roll and _id. The '_id' field is always d...
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PostgreSQL return result set as JSON array?

... TL;DR SELECT json_agg(t) FROM t for a JSON array of objects, and SELECT json_build_object( 'a', json_agg(t.a), 'b', json_agg(t.b) ) FROM t for a JSON object of arrays. List of objects This section de...
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jQuery - select all text from a textarea

...can I make it so when you click inside a textarea, its entire content gets selected? 6 Answers ...
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MySQL Query to select data from last week?

Hi I have a table with a date field and some other information. I want to select all entries from the past week, (week start from Sunday). ...
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SQL Server Insert if not exists

..., Assunto, Data) VALUES (@_DE, @_ASSUNTO, @_DATA) WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos WHERE De = @_DE AND Assunto = @_ASSUNTO AND Data = @_DATA); END replace with BEGIN IF NOT EXISTS (SELECT * FROM EmailsRecebidos ...
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Bootstrap select dropdown list placeholder

... Yes just "selected disabled" in the option. <select> <option value="" selected disabled>Please select</option> <option value="">A</option> <option value="">B</option> <optio...
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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)

...irm this - I just updated a query with 4 joins on a 168,000 row database. Selecting just the first 100 rows with a SQL_CALC_FOUND_ROWS took over 20 seconds; using a separate COUNT(*) query took under 5 seconds (for both count + results queries). – Sam Dufel Ju...
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Select top 10 records for each category

... If you are using SQL 2005 you can do something like this... SELECT rs.Field1,rs.Field2 FROM ( SELECT Field1,Field2, Rank() over (Partition BY Section ORDER BY RankCriteria DESC ) AS Rank FROM table ) rs WHERE Rank <= 10 If y...