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CROSS JOIN vs INNER JOIN in SQL
...ame situation.
These 2 examples will return the same result:
Cross join
select * from table1 cross join table2 where table1.id = table2.fk_id
Inner join
select * from table1 join table2 on table1.id = table2.fk_id
Use the last method
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...c
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But what should the value of b show on each of these two rows? There are three possibilities in each case, and no...
Insert results of a stored procedure into a temporary table
How do I do a SELECT * INTO [temp table] FROM [stored procedure] ? Not FROM [Table] and without defining [temp table] ?
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How do I set the selected item in a comboBox to match my string using C#?
..." and my comboBox contains test1 , test2 , and test3 . How do I set the selected item to "test1"? That is, how do I match my string to one of the comboBox items?
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How do I get a list of column names from a psycopg2 cursor?
I would like a general way to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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How to select all instances of a variable and edit variable name in Sublime
If I select a variable (not just any string) in my code, all other instances of that variable get a stroke (white outline) around them:
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How disable Copy, Cut, Select, Select All in UITextView
The UITextView 's Copy, Cut, Select, Select All functionality is shown by default when I press down on the screen. But, in my project the UITextField is only read only. I do not require this functionality. Please tell me how to disable this feature.
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Iterate through options
I have a <select> element in HTML. This element represents a drop down list. I'm trying to understand how to iterate through the options in the <select> element via JQuery.
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Is the LIKE operator case-sensitive with MSSQL Server?
...en-us/library/ms144250(v=sql.105).aspx
(a) To check a instance collation
select serverproperty('collation')
(b) To check a database collation
select databasepropertyex('databasename', 'collation') sqlcollation
(c) To create a database using a different collation
create database exampledataba...
Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...