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Select a Dictionary with LINQ
I have used the "select" keyword and extension method to return an IEnumerable<T> with LINQ, but I have a need to return a generic Dictionary<T1, T2> and can't figure it out. The example I learned this from used something in a form similar to the following:
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Selectively revert or checkout changes to a file in Git?
... @Jan Do other version control systems' revert command allow you to select which changes within a file are reverted? Genuinely asking, as I only have experience with CVS and Git. In Git, git checkout -- path/to/file is a single command that reverts all changes in that file, but this is not th...
Delete all Duplicate Rows except for One in MySQL? [duplicate]
...te.
INSERT INTO tempTableName(cellId,attributeId,entityRowId,value)
SELECT DISTINCT cellId,attributeId,entityRowId,value
FROM tableName;
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How to display the function, procedure, triggers source code in postgresql?
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For function:
you can query the pg_proc view , just as the following
select proname,prosrc from pg_proc where proname= your_function_name;
Another way is that just execute the commont \df and \ef which can list the functions.
skytf=> \df
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Is there any performance gain in indexing a boolean field?
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It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
Visual Studio hot keys change occasionally, specifically F6 vs Ctrl-Shift-B for building. WHY?
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This is because you might have selected "General Development Settings" as your default environment settings for your Visual Studio (which usually we do on the first launch of VS after installing it as it pops up a dialogue box to choose default environment...
How to alter SQL in “Edit Top 200 Rows” in SSMS 2008
...008 Management Studio, when I right click on a database table and choose " Select Top 100 Rows ", I can then e.g. easily add a "ORDER BY " statement to the SQL. That works fine .
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Jquery select all elements that have $jquery.data()
Select elements that i have previously set with jquery.data();
7 Answers
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Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
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Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...