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typecast string to integer - Postgres
...ur value is an empty string, you can use NULLIF to replace it for a NULL:
SELECT
NULLIF(your_value, '')::int
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Android - Set max length of logcat messages
...e { Log.v(TAG, sb); } to also print the log when the message is <= 4000 chars long
– Bojan Radivojevic Bomber
Apr 26 '14 at 21:45
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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...
How do I iterate through the alphabet?
In Python, could I simply ++ a char? What is an efficient way of doing this?
2 Answers
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Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Trigger change event of dropdown
...wns, the best way to do it is to have a script that returns the a prebuilt select box and an AJAX call that requests it.
Here is the documentation for jQuery's Ajax method if you need it.
$(document).ready(function(){
$('#countrylist').change(function(e){
$this = $(e.target);
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Emacs on Mac OS X Leopard key bindings
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⌘ + → - move to end of current line
Shift + any of the above extend selection by appropriate amount
Click then drag - select text
Double-click then drag - select text, wrapping to word ends
Triple-click then drag - select text, wrapping to paragraph ends
Shift + Select text with mouse - add...
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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T-SQL get SELECTed value of stored procedure
...UTPUT parameter and a result set
ALSO, watch out if you use the pattern: SELECT @Variable=column FROM table ...
if there are multiple rows returned from the query, your @Variable will only contain the value from the last row returned by the query.
RETURN VALUE
since your query returns an int fie...