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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...
Get index of selected option with jQuery
I'm a little bit confused about how to get an index of a selected option from a HTML <select> item.
7 Answers
...
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...
Converting RGB to grayscale/intensity
...th 32 bits i.e. 4 bytes per pixel
unsigned int fourBytes;
unsigned char r,g,b;
for (int index=0;index<width*height;index++)
{
fourBytes=pntrBWImage[index];//caches 4 bytes at a time
r=(fourBytes>>16);
g=(fourBytes>>8);
...
IntelliJ IDEA way of editing multiple lines
...ossibility to edit multiple lines.
Use:
Alt + Shift + Mouse click
for selection. More about this new improvement in IntelliJ blogpost here. Very useful feature.
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...
How can I run MongoDB as a Windows service?
...he following error: Cannot open MongoDB service
on computer '.'.
At line:1 char:1
+ Start-Service MongoDB
+ ~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : OpenError: (System.ServiceProcess.ServiceController:ServiceController) [Start-Service],
ServiceCommandException
+ FullyQualifiedError...
How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
Can you animate a height change on a UITableViewCell when selected?
... I would like it so that when the user clicks on a particular person (thus selecting the cell), the cell grows in height to display several UI controls for editing the properties of that person.
...
How to set variables in HIVE scripts
...riable substitution.
e.g.
hive> set CURRENT_DATE='2012-09-16';
hive> select * from foo where day >= ${hiveconf:CURRENT_DATE}
similarly, you could pass on command line:
% hive -hiveconf CURRENT_DATE='2012-09-16' -f test.hql
Note that there are env and system variables as well, so you can r...
Calculate a Running Total in SQL Server
... somewhat limited.
Oracle (and ANSI-SQL) allow you to do things like:
SELECT somedate, somevalue,
SUM(somevalue) OVER(ORDER BY somedate
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
AS RunningTotal
FROM Table
SQL Server gives you no clean solution to this problem. My ...