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What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
...ent attribute. Otherwise, (valid at least for PG) you might get ERROR: for SELECT DISTINCT, ORDER BY expressions must appear in select list
– long
Apr 21 at 14:08
add a commen...
Get list of databases from SQL Server
...
Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
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...
Eclipse fonts and background color
...→ General → Editors → Text Editors
Browse Appearance color options
Select background color options, uncheck default, change to black
Select background color options, uncheck default, change to colour of choice
To change text colours
Open Java → Editor → Syntax Colouring
Select ele...
How to get a microtime in Node.js?
...
Please check the time units when converting seconds to microseconds. console.log(hrTime[0] * 1000000 + hrTime[1] / 1000)
– itaifrenkel
May 5 '14 at 16:05
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Dynamic SELECT TOP @var In SQL Server
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SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
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Check for changes to an SQL Server table?
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Take a look at the CHECKSUM command:
SELECT CHECKSUM_AGG(BINARY_CHECKSUM(*)) FROM sample_table WITH (NOLOCK);
That will return the same number each time it's run as long as the table contents haven't changed. See my post on this for more information:
CHECKSUM...
Find an item in List by LINQ?
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If you want the index of the element, this will do it:
int index = list.Select((item, i) => new { Item = item, Index = i })
.First(x => x.Item == search).Index;
// or
var tagged = list.Select((item, i) => new { Item = item, Index = i });
int index = (from pair in tagged
...
How to increase font size in the Xcode editor?
...)
Go to XCode > Preferences > Fonts & Color
From the 'Theme' box select the theme you want to modify (or select the theme you want to modify and click the "+" button at the bottom of the theme list to clone it first for backup, for there is no undo option)
In the source editor box there is...
How does MySQL process ORDER BY and LIMIT in a query?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ...