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MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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Why em instead of px?
I heard you should define sizes and distances in your stylesheet with em instead of in pixels. So the question is why should I use em instead of px when defining styles in css? Is there a good example that illustrates this?
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SQL - find records from one table which don't exist in another
...shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alternatively (thanks to Alterlife)
SELECT *
FROM Call
WHERE NOT EXISTS
(SELECT *
FROM Phone_book
WHERE Phone_book.phon...
How do you check what version of SQL Server for a database using TSQL?
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Try
SELECT @@VERSION
or for SQL Server 2000 and above the following is easier to parse :)
SELECT SERVERPROPERTY('productversion')
, SERVERPROPERTY('productlevel')
, SERVERPROPERTY('edition')
From: http://support....
Insert into … values ( SELECT … FROM … )
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Try:
INSERT INTO table1 ( column1 )
SELECT col1
FROM table2
This is standard ANSI SQL and should work on any DBMS
It definitely works for:
Oracle
MS SQL Server
MySQL
Postgres
SQLite v3
Teradata
DB2
Sybase
Vertica
HSQLDB
H2
AWS RedShift
SA...
jQuery - select all text from a textarea
...can I make it so when you click inside a textarea, its entire content gets selected?
6 Answers
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Android Spinner: Get the selected item change event
How can you set the event listener for a Spinner when the selected item changes?
16 Answers
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How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
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 ...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...