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Where to put include statements, header or source?
...g.
typedef union {
unsigned long l;
unsigned short lw[2];
unsigned char lb[4];
} U_QUAD;
(Yes, I know I'd be in trouble if I moved to a big-endian architecture, but since my compiler doesn't allow anonymous structs in unions, using named identifiers for the bytes within the union would req...
Split function equivalent in T-SQL?
...AR(2048) = 'Mike/John/Miko/Matt'; DECLARE CaracString NVARCHAR(1) = '/'; SELECT * FROM dbo.FnSplitString (VarString, CaracString)
– fernando yevenes
Feb 8 '19 at 15:57
ad...
quick random row selection in Postgres
...
You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor he...
jQuery get specific option tag text
...Here is this answer expanded if you want to get the value dynamically: var selectValue = document.getElementById('list').value; var selectOption = $("#list option[value=" + selectValue + "]").text(); ///good example nickf.
– Kevin Florida
Apr 5 '11 at 13:48
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PHP method chaining?
...imed at creating a DSL. Ex: $foo->setBar(1)->setBaz(2) vs $table->select()->from('foo')->where('bar = 1')->order('ASC). The latter spans multiple objects.
– Gordon
Sep 16 '10 at 7:32
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Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
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Generate a random number in the range 1 - 10
... 1 and 10 you mean any float that is >= 1 and < 10, then it's easy:
select random() * 9 + 1
This can be easily tested with:
# select min(i), max(i) from (
select random() * 9 + 1 as i from generate_series(1,1000000)
) q;
min | max
-----------------+------------------...
JComboBox Selection Change Listener?
...istener() will work, too. You may get 2 ItemEvents, though, one for the deselection of the previously selected item, and another for the selection of the new item. Just don't use both event types!
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...dn't want the overhead of a function. I came up with the following query:
SELECT myfield::integer FROM mytable WHERE myfield ~ E'^\\d+$';
Postgres shortcuts its conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regex...
Long vs Integer, long vs int, what to use and when?
...//docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html
byte, char .. 1B .. 8b
short int .. 2B .. 16b
int .. .. .. .. 4B .. 32b
long int .. 8B .. 64b
C .. just mess: https://en.wikipedia.org/wiki/C_data_types
short .. .. 16b
int .. .. .. 16b ... wtf?!?!
long .. .. 32b
long long .. ...