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Why does PostgreSQL perform sequential scan on indexed column?
...
If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
Use gulp to select and move directories and their files
... },
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SQL update query using joins
...common table expression (since you're already on SQL 2005):
with cte as (
select
im.itemid
,im.sku as iSku
,gm.SKU as GSKU
,mm.ManufacturerId as ManuId
,mm.ManufacturerName
,im.mf_item_number
,mm.ManufacturerID
, <your other field>
from
item_master im, gro...
Is there a list of Pytz Timezones?
... called America/New_York.
If you programatically want to create this list from the zoneinfo database you can compile it from the zone.tab file in the zoneinfo database. I don't think pytz has an API to get them, and I also don't think it would be very useful.
...
Is it possible to open a Windows Explorer window from PowerShell?
...tion looking for a way to open an Explorer window from PowerShell and also select a file. I'm adding this answer in case others come across it for the same reason.
To launch Explorer and select a file, use Invoke-Expression:
Invoke-Expression "explorer '/select,$filePath'"
There are probably oth...
When should I use a table variable vs temporary table in sql server?
... source for the data inserted to the table is from a potentially expensive SELECT statement then consider that using a table variable will block the possibility of this using a parallel plan.
If you need the data in the table to survive a rollback of an outer user transaction then use a table variab...
Xcode 4 - “Valid signing identity not found” error on provisioning profiles on a new Macintosh insta
...machine, launch Xcode and do this:
Open the Organizer (Shift-Command-2).
Select the Devices tab.
Choose Developer Profile in the upper-left corner under LIBRARY, which may be under the heading library or under a heading called TEAMS.
Choose Export near the bottom left side of
the window. Xcode as...
Differences between MySQL and SQL Server [closed]
...mplementations.
For example, take a look at the top-n section. In MySQL:
SELECT age
FROM person
ORDER BY age ASC
LIMIT 1 OFFSET 2
In SQL Server (T-SQL):
SELECT TOP 3 WITH TIES *
FROM person
ORDER BY age ASC
share
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Using module 'subprocess' with timeout
...
In Python 3.3+:
from subprocess import STDOUT, check_output
output = check_output(cmd, stderr=STDOUT, timeout=seconds)
output is a byte string that contains command's merged stdout, stderr data.
check_output raises CalledProcessError on...
How to use 'find' to search for files created on a specific date? [closed]
...be set to the number of days between then and today. (Update: subtract one from the result to align with find's date rounding.)
So, to find any file modified on September 24th, 2008, the command would be:
find . -type f -mtime $(( ( $(date +%s) - $(date -d '2008-09-24' +%s) ) / 60 / 60 / 24 - 1 ))...