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postgresql: INSERT INTO … (SELECT * …)
I'm not sure if its standard SQL:
6 Answers
6
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Select DISTINCT individual columns in django?
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It's quite simple actually if you're using PostgreSQL, just use distinct(columns) (documentation).
Productorder.objects.all().distinct('category')
Note that this feature has been included in Django since 1.4
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Default string initialization: NULL or Empty? [closed]
...is no way to accurately represent, say, a varchar( 100 ) NOT NULL field in SQL Server using a C# type.
Other languages, such as Spec #, do allow this.
In my opinion, C#'s inability to define a string that doesn't allow null is just as bad as its previous inability to define an int that does allow ...
Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT
I am fairly new to MySQL and I am getting a pretty interesting error on which I cannot find any help via google and the stackoverflow search.
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What does java:comp/env/ do?
... lookup using "java:comp/env/foo". Have a look at blog.cherouvim.com/javax-sql-datasource-exposed-through-jndi
– cherouvim
Nov 5 '10 at 7:57
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How do I print the full value of a long string in gdb?
...r_string. The output might be a bit harder to read. For example printing a SQL query results in:
(gdb) x/300sb stmt.c_str()
0x9cd948: "SELECT article.r"...
0x9cd958: "owid FROM articl"...
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How do I insert datetime value into a SQLite database?
I am trying to insert a datetime value into a SQLite database. It seems to be sucsessful but when I try to retrieve the value there is an error:
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Right query to get the current number of connections in a PostgreSQL DB
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Note that when the postgres command line tool, PSQL is used for executing this query, the total number of connections is the result of this query - 1 since the psql connection made is also included as a connection
– neonidian
Dec 13 '...
How to 'insert if not exists' in MySQL?
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use INSERT IGNORE INTO table
see http://bogdan.org.ua/2007/10/18/mysql-insert-if-not-exists-syntax.html
there's also INSERT … ON DUPLICATE KEY UPDATE syntax, you can find explanations on dev.mysql.com
Post from bogdan.org.ua according to Google's webcache:
18th October 2007
To...
Does the order of LINQ functions matter?
...WHERE clause first) for LINQ-to-XML, but faster the first time for LINQ-to-SQL.
To find out precisely what the performance difference is, you'll most likely want to profile your application. As ever with such things, though, premature optimisation is not usually worth the effort -- you may well fin...