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Fastest check if row exists in PostgreSQL
...
Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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Resetting a multi-stage form with jQuery
...n, :submit, :reset, :hidden')
.val('')
.removeAttr('checked')
.removeAttr('selected');
Which might work for a lot of cases, including for the OP, but as pointed out in the comments and in other answers, will clear radio/checkbox elements from any value attributes.
A more correct answer (but not per...
Setting custom UITableViewCells height
...Size:14.0f] constrainedToSize:constraintSize lineBreakMode:UILineBreakModeCharacterWrap]
if ( neededSize.height <= 18)
return 45
else return neededSize.height + 45
//18 is the size of your text with the requested font (systemFontOfSize 14). if you change fonts you have a different number t...
Case insensitive searching in Oracle
...NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', 'NLS_SORT');
NLS_SORT
BINARY
NLS_COMP
BINARY
SQL>
SQL> SELECT CASE WHEN 'abc'='ABC' THEN 1 ELSE 0 END AS GOT_MATCH
2 FROM DUAL;
...
'IF' in 'SELECT' statement - choose output value based on column values
...
SELECT id,
IF(type = 'P', amount, amount * -1) as amount
FROM report
See http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of...
Fast ceiling of an integer division in C / C++
... return res.rem ? (res.quot + 1) : res.quot;
}
int main(int, const char**)
{
std::cout << "10 / 5 = " << div_ceil(10, 5) << std::endl;
std::cout << "11 / 5 = " << div_ceil(11, 5) << std::endl;
return 0;
}
...
Character reading from file in Python
...rom Unicode, then there's really no direct way to do so, since the Unicode characters won't necessarily exist in ASCII.
If you're trying to convert to an ASCII string, try one of the following:
Replace the specific unicode chars with ASCII equivalents, if you are only looking to handle a few spe...
Select rows which are not present in other table
...task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
);
Also consider:
What is easier to read in EXISTS...
How to declare a variable in a PostgreSQL query
...ows you to return a table of temporary values.
WITH master_user AS (
SELECT
login,
registration_date
FROM users
WHERE ...
)
SELECT *
FROM users
WHERE master_login = (SELECT login
FROM master_user)
AND (SELECT registration_date
FROM ma...
How do I (or can I) SELECT DISTINCT on multiple columns?
...
SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c
It's a good idea to get used to the GROUP BY syntax, as it's more powerful.
For your query, I'd do it like this:
UPDATE sale...