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postgresql - sql - count of `true` values
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Since PostgreSQL 9.4 there's the FILTER clause, which allows for a very concise query to count the true values:
select count(*) filter (where myCol)
from tbl;
The above query is a bad example in that a simple WHERE clause would suffice...
How do you use variables in a simple PostgreSQL script?
For example, in MS-SQL, you can open up a query window and run the following:
10 Answers
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Rename MySQL database [duplicate]
.... Now I need to change database name to sunhrm . But, It is disabled in MySQL workbench. Can I do that on the Linux server itself?
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What is your naming convention for stored procedures? [closed]
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Here's some clarification about the sp_ prefix issue in SQL Server.
Stored procedures named with the prefix sp_ are system sprocs stored in the Master database.
If you give your sproc this prefix, SQL Server looks for them in the Master database first, then the context database,...
Linq to EntityFramework DateTime
...ntity Framework, your predicates inside the Where clause get translated to SQL. You're getting that error because there is no translation to SQL for DateTime.Add() which makes sense.
A quick work-around would be to read the results of the first Where statement into memory and then use LINQ to Objec...
Why does Oracle 9i treat an empty string as NULL?
...at doesn't do much to tell me why this is the case. As I understand the SQL specifications, ' ' is not the same as NULL -- one is a valid datum, and the other is indicating the absence of that same information.
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Is it possible to use the SELECT INTO clause with UNION [ALL]?
In SQL Server this inserts 100 records, from the Customers table into tmpFerdeen :-
8 Answers
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How to get last inserted id?
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For SQL Server 2005+, if there is no insert trigger, then change the insert statement (all one line, split for clarity here) to this
INSERT INTO aspnet_GameProfiles(UserId,GameId)
OUTPUT INSERTED.ID
VALUES(@UserId, @GameId)
F...
GROUP BY with MAX(DATE) [duplicate]
...'s answer will tend to perform less I/O. The analytic function allows the SQL to process the the table in a single pass, whereas Oliver's solution requires multiple passes.
– Adam Musch
Aug 16 '10 at 14:33
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Create a nonclustered non-unique index within the CREATE TABLE statement with SQL Server
It is possible to create a primary key or unique index within a SQL Server CREATE TABLE statement. Is it possible to create a non-unique index within a CREATE TABLE statement?
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