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Find the number of columns in a table
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SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
share
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How do I (or can I) SELECT DISTINCT on multiple columns?
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SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c
It's a good idea to get used to the GROUP BY syntax, as it's more powerful.
For your query, I'd do it like this:
UPDATE sale...
How to select only the first rows for each unique value of a column
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A very simple answer if you say you don't care which address is used.
SELECT
CName, MIN(AddressLine)
FROM
MyTable
GROUP BY
CName
If you want the first according to, say, an "inserted" column then it's a different query
SELECT
M.CName, M.AddressLine,
FROM
(
SELECT
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How to have a default option in Angular.js select box
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You can simply use ng-init like this
<select ng-init="somethingHere = options[0]"
ng-model="somethingHere"
ng-options="option.name for option in options">
</select>
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How to set Sqlite3 to be case insensitive when string comparing?
I want to select records from sqlite3 database by string matching. But if I use '=' in the where clause, I found that sqlite3 is case sensitive. Can anyone tell me how to use string comparing case-insensitive?
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How to remove an iOS app from the App Store
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What you need to do is this.
Go to “Manage Your Applications” and select the app.
Click “Rights and Pricing” (blue button at the top right.
Below the availability date and price tier section, you should see a grid of checkboxes for the various countries your app is available in. Click t...
Counting DISTINCT over multiple columns
... function turns the ints into varchars to make the distinct more reliable
SELECT COUNT(DISTINCT (CHECKSUM(DocumentId,DocumentSessionId)) + CHECKSUM(REVERSE(DocumentId),REVERSE(DocumentSessionId)) )
FROM DocumentOutPutItems
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Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
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postgresql - sql - count of `true` values
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SELECT COALESCE(sum(CASE WHEN myCol THEN 1 ELSE 0 END),0) FROM <table name>
or, as you found out for yourself:
SELECT count(CASE WHEN myCol THEN 1 END) FROM <table name>
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How do I style a dropdown with only CSS?
Is there a CSS-only way to style a <select> dropdown?
24 Answers
24
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