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What's the recommended approach to resetting migration history using Django South?
...ion and fake-applies it (since your database already has the corresponding tables). There's no need to drop all the app tables during the process.
Here's what I'm doing on my dev + production server when I need to get rid of all these unneeded dev migrations:
Make sure we have the same DB sche...
When and why are database joins expensive?
...nality when (if) they set up indexes.
It is important to understand that table scans (examination of every row in a table in the course of producing a join) are rare in practice. A query optimiser will choose a table scan only when one or more of the following holds.
There are fewer than 200 row...
Save PL/pgSQL output from PostgreSQL to a CSV file
...rticular directory, for instance, and the filename might have to have a suitable prefix or extension.
Which tables should the user be able to read/write in the database? This would normally be defined by GRANTs in the database, but the function is now running as a superuser, so tables which would no...
What's the best way to store co-ordinates (longitude/latitude, from Google Maps) in SQL Server?
I'm designing a table in SQL Server 2008 that will store a list of users and a Google Maps co-ordinate (longitude & latitude).
...
C# switch statement limitations - why?
...a CIL switch statement which is indeed a constant time branch using a jump table. However, in sparse cases as pointed out by Ivan Hamilton the compiler may generate something else entirely.
This is actually quite easy to verify by writing various C# switch statements, some sparse, some dense, and ...
Why are joins bad when considering scalability?
...ted comparison for a join is now much smaller and potentially pre-indexed.
Table partitions (helps with large data sets by spreading the load out to multiple disks, or limiting what might have been a table scan down to a partition scan)
OLAP (pre-computes results of certain kinds of queries/joins. I...
PHP PDO: charset, set names?
...llation by clicking your database and choose operations. If you try create tables with another collation than your database, your tables will end up with the database collation anyways.
So make sure the collation for your database is right before creating tables. Hope this saves someone a few hours...
Fetch the row which has the Max value for a column
Table:
35 Answers
35
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How do I find duplicate values in a table in Oracle?
...or a given column and the count of their occurrences in an Oracle database table?
13 Answers
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Is SQL or even TSQL Turing Complete?
...nFuck" DataBase.
-- CREATE DATABASE BrainFuck;
-- Creates the Source code table
DECLARE @CodeTable TABLE (
[Id] INT IDENTITY(1,1) PRIMARY KEY NOT NULL,
[Command] CHAR(1) NOT NULL
);
-- Populate the source code into CodeTable
DECLARE @CodeLen INT = LEN(@Code);
DECLARE @CodePos INT = 0;...