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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
I've heard that SELECT * is generally bad practice to use when writing SQL commands because it is more efficient to SELECT columns you specifically need.
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How to check if command line tools is installed
...ars in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is installed and if yes to find the version installed?
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Unioning two tables with different number of columns
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Add extra columns as null for the table having less columns like
Select Col1, Col2, Col3, Col4, Col5 from Table1
Union
Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2
share
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PostgreSQL return result set as JSON array?
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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...
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
...These pictures don't do it for me. Why is the top right picture not simply SELECT * FROM TableA;? Why is the top left picture not simply SELECT * FROM TableB;? Why is the top middle picture not SELECT * FROM A INTERSECT SELECT * FROM B ? etc
– onedaywhen
Sep 9 ...
Is it possible to specify condition in Count()?
...an use the fact that the count aggregate only counts the non-null values:
select count(case Position when 'Manager' then 1 else null end)
from ...
You can also use the sum aggregate in a similar way:
select sum(case Position when 'Manager' then 1 else 0 end)
from ...
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Blank HTML SELECT without blank item in dropdown list
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Just use disabled and/or hidden attributes:
<option selected disabled hidden style='display: none' value=''></option>
selected makes this option the default one.
disabled makes this option unclickable.
style='display: none' makes this option not displayed in older ...
SQL Server SELECT INTO @variable?
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You cannot SELECT .. INTO .. a TABLE VARIABLE. The best you can do is create it first, then insert into it. Your 2nd snippet has to be
DECLARE @TempCustomer TABLE
(
CustomerId uniqueidentifier,
FirstName nvarchar(100),
LastNa...
Insert Data Into Temp Table with Query
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SELECT *
INTO #Temp
FROM
(SELECT
Received,
Total,
Answer,
(CASE WHEN application LIKE '%STUFF%' THEN 'MORESTUFF' END) AS application
FROM
FirstTable
WHERE
Recieved = 1 AND
applicati...
How do I format date and time on ssrs report?
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Hope this helps:
SELECT convert(varchar, getdate(), 100) -- mon dd yyyy hh:mmAM
SELECT convert(varchar, getdate(), 101) -- mm/dd/yyyy – 10/02/2008
SELECT convert(varchar, getdate(), 102) -- yyyy.mm.dd – 2008.10.02 ...