大约有 41,000 项符合查询结果(耗时:0.0515秒) [XML]
Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
...
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!
share
|
...
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
-----------------+------------------...
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...
MySQL select with CONCAT condition
...available within the query itself.
You can either repeat the expression:
SELECT neededfield, CONCAT(firstname, ' ', lastname) as firstlast
FROM users
WHERE CONCAT(firstname, ' ', lastname) = "Bob Michael Jones"
or wrap the query
SELECT * FROM (
SELECT neededfield, CONCAT(firstname, ' ', last...
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 .. ...
How to get object size in memory? [duplicate]
...would know, Int32 and float are four
bytes, double and DateTime 8 bytes, char is actually two bytes (not
one byte), and so on. String is a bit more complex, 2*(n+1), where n
is the length of the string. For objects, it will depend on their
members: just sum up the memory requirement of all i...
How can I echo HTML in PHP?
...
@MhdSyrwan just random chars, you can read more here php.net/manual/en/…
– lfx
Sep 23 '11 at 18:22
1
...
jQuery UI: Datepicker set year range dropdown to 100 years
...wn: either relative to today's year ("-nn:+nn"), relative to the currently selected year ("c-nn:c+nn"), absolute ("nnnn:nnnn"), or combinations of these formats ("nnnn:-nn"). Note that this option only affects what appears in the drop-down, to restrict which dates may be selected use the minDate and...
How disable Copy, Cut, Select, Select All in UITextView
The UITextView 's Copy, Cut, Select, Select All functionality is shown by default when I press down on the screen. But, in my project the UITextField is only read only. I do not require this functionality. Please tell me how to disable this feature.
...