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What's the best practice for primary keys in tables?
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In some cases with SQL server 2005/2008 the natural (text) key can be faster than an int key. I have an app with a 7-8 character friendly code that we use as the primary key and that was faster (and often more convenient) than an int surrogate....
Avoid web.config inheritance in child web application using inheritInChildApplications
...ecause the keys AND values were always the same. Yesterday we updated our SQL connection strings to include the Application Name in the connection string. This made the string unique and all of sudden started to fail.
Without doing any research on the exact reason for this, I have to assume that ...
Getting vertical gridlines to appear in line plot in matplotlib
...id lines are appearing by default. I am using a pandas.DataFrame from an sql query in python to generate a line plot with dates on the x-axis. I'm not sure why they do not appear on the dates and I have tried to search for an answer to this but couldn't find one.
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What are five things you hate about your favorite language? [closed]
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Wow, I'm surprised that SQL hasn't made it up here yet. Guess that means nobody loves it :)
Inconsistent syntax across implementations
Subtle code differences can have massive performance ramifications for seemingly obscure reasons
Poor support fo...
How to escape a JSON string to have it in a URL?
...t you do from here on, you might be opening yourself for a security issue (SQL injection, etc.)
– Tit Petric
Jul 27 '17 at 7:25
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How to Sync iPhone Core Data with web server, and then push to other devices? [closed]
...base mobile. This basically does all you want. (http://www.couchbase.com/nosql-databases/couchbase-mobile)
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How to reset postgres' primary key sequence when it falls out of sync?
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-- Login to psql and run the following
-- What is the result?
SELECT MAX(id) FROM your_table;
-- Then run...
-- This should be higher than the last result.
SELECT nextval('your_table_id_seq');
-- If it's not higher... run this set the ...
Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
Using MSSQL2005, can I truncate a table with a foreign key constraint if I first truncate the child table (the table with the primary key of the FK relationship)?
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How to change the foreign key referential action? (behavior)
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Example:
I have a UserDetails table refers to Users table:
mysql> SHOW CREATE TABLE UserDetails;
:
:
`User_id` int(11) DEFAULT NULL,
PRIMARY KEY (`Detail_id`),
KEY `FK_User_id` (`User_id`),
CONSTRAINT `FK_User_id` FOREIGN KEY (`User_id`) REFERENCES `Users` (`User_id`)
:
:
F...
Create Django model or update if exists
...default, from the docs:
Django abstracts the need to use INSERT or UPDATE SQL statements.
Specifically, when you call save(), Django follows this algorithm:
If the object’s primary key attribute is set to a value that evaluates
to True (i.e., a value other than None or the empty string), Django
e...