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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...
Can I use CASE statement in a JOIN condition?
...ns a value from the THEN portion of the clause. You could use it thusly:
SELECT *
FROM sys.indexes i
JOIN sys.partitions p
ON i.index_id = p.index_id
JOIN sys.allocation_units a
ON CASE
WHEN a.type IN (1, 3) AND a.container_id = p.hobt_id THEN 1
...
Xcode 6 Bug: Unknown class in Interface Builder file
... this issue when using Xcode 6 beta 4.
To resolve this issue, you need to select each of your custom class objects in Storyboard (this includes any custom views, even the custom view controllers themselves).
Then with those objects selected, open the identity inspector and under "Custom Class" you...
Is 1.0 a valid output from std::generate_canonical?
...alues happen to round up to IEEE 1.0f but that's just unavoidable when you cast them to IEEE floats. If you want pure mathematical results, use a symbolic computation system; if you are trying to use IEEE floating-point to represent numbers that are within eps of 1, you are in a state of sin.
...
Xcode 4, Core Data Model Version - Set Current Version
...d "View" button at the top right of the window).
In the Utilities sidepane select the File inspector (little paper icon on the top left)
You will see "Versioned Core Data Model" as a group so just change the "Current" drop-down to your new version.
...
How to check date of last change in stored procedure or function in SQL server
...
SELECT name, create_date, modify_date
FROM sys.objects
WHERE type = 'P'
ORDER BY modify_date DESC
The type for a function is FN rather than P for procedure. Or you can filter on the name column.
...
How to exclude specific folders or files from validation in Eclipse?
...ge below)
Note: In Eclipse Indigo you have to Right click the folder and select properties and then select resource in the left navigation.
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How can I get a list of all functions stored in the database of a particular schema in PostgreSQL?
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SELECT n.nspname as "Schema", p.proname as "Name", pg_catalog.pg_get_function_result(p.oid) as "Result data type", pg_catalog.pg_get_function_arguments(p.oid) as "Argument data types", CASE WHEN p.proisagg THEN 'agg'...
When to use actors instead of messaging solutions such as WebSphere MQ or Tibco Rendezvous?
...no-brainer. However Akka's Java bindings are not very Java-ish and require casting due to Scala's type system.
Also in Java people don't typically make immutable objects which I recommend you do for messaging. Consequently its very easy in Java to accidentally do something using Akka that will not...
Check for changes to an SQL Server table?
...
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...