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What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
SQL Server: Examples of PIVOTing String data
...l as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
...
Datetime equal or greater than today in MySQL
...
SELECT * FROM users WHERE created >= CURDATE();
But I think you mean created < today
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SQL Server SELECT INTO @variable?
...
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...
Best way to test SQL queries [closed]
...value, and all values are consecutive:
create view cm_absolute_month as
select *, year * 12 + month as absolute_month from month_value;
Now what we have to test is inherent in our spec, namely that for any tuple (year, month), there is one and only one (absolute_month), and that (absolute_month...
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.
...
How can I convert tabs to spaces in every file of a directory?
...s on each line;
-t 4 means that each tab will be converted to 4 whitespace chars (8 by default).
sponge is from the moreutils package, and avoids clearing the input file.
Finally, you can use gexpand on OSX, after installing coreutils with Homebrew (brew install coreutils).
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Select statement to find duplicates on certain fields
...get the list of fields for which there are multiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There sh...
jQuery see if any or no checkboxes are selected
I know how to see if an individual checkbox is selected or not.
8 Answers
8
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Adding HTML entities using CSS content
... edited Apr 23 '18 at 5:15
Charlie
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answered Oct 10 '08 at 7:27
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