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How to find the size of an array in postgresql
...ing PostgreSQL 9.4 or higher, you can use cardinality:
SELECT cardinality(id) FROM example;
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How can I temporarily disable a foreign key constraint in MySQL?
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This worked for me after trying the 'best answer' didn't work for me. Perhaps an explanation of the difference could be added.
– hexnet
Aug 27 '15 at 12:37
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Android: How to enable/disable option menu item on button click?
...change the Options Menu any time after
it's first created, you must override
the onPrepareOptionsMenu() method.
This passes you the Menu object as it
currently exists. This is useful if
you'd like to remove, add, disable, or
enable menu items depending on the
current state of your appl...
Calling JMX MBean method from a shell script
... (and no development since 2006 it looks like)
Groovy script and JMX - provides some really powerful JMX functionality but requires groovy and other library setup.
JManage command line
functionality - (downside is
that it requires a running JManage
server to proxy commands through)
Groovy JMX Exam...
PostgreSQL create table if not exists
...to work around it:
CREATE OR REPLACE FUNCTION create_mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM pg_catalog.pg_tables
WHERE schemaname = 'myschema'
AND tablename = 'mytable') THEN
RAISE NOTICE 'Table myschema.mytable a...
How to solve PHP error 'Notice: Array to string conversion in…'
...k you so much for your clear explanation. It prints out what exactly you said. It means my array has been already sent to the PHP file. Seems I can use without without any problem. Thankz again.
– t4thilina
Nov 16 '13 at 11:02
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Command line for looking at specific port
... Also worth mentioning the -o flag (i.e. -nao here) to include the PID of the process using the port.
– Steve Chambers
Nov 28 '17 at 10:29
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Why are nested weights bad for performance? Alternatives?
...ted weights are bad for performance because:
Layout weights require a widget to be measured twice. When a
LinearLayout with non-zero weights is nested inside another
LinearLayout with non-zero weights, then the number of measurements
increase exponentially.
It's better to use RelativeLay...
Click outside menu to close in jquery
...enu that shows on a click, as per business requirements. The menu becomes hidden again after you mouse away from it.
15 Ans...
Check if a row exists, otherwise insert
...row for each flight? If so:
IF EXISTS (SELECT * FROM Bookings WHERE FLightID = @Id)
BEGIN
--UPDATE HERE
END
ELSE
BEGIN
-- INSERT HERE
END
I assume what I said, as your way of doing things can overbook a flight, as it will insert a new row when there are 10 tickets max and you are booking 2...