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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
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For the UPDATE
Use:
UPDATE table1
SET col1 = othertable.col2,
col2 = othertable.col3
FROM othertable
WHERE othertable.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't ...
Select statement to find duplicates on certain fields
...ltiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There should be a criterion for deciding how you defi...
django syncdb and an updated model
...ngo currently does not do this automatically. Your options are:
Drop the table from the database, then recreate it in new form using syncdb.
Print out SQL for the database using python manage.py sql (appname), find the added line for the field and add it manually using alter table SQL command. (Th...
Order a MySQL table by two columns
How do I sort a MySQL table by two columns?
5 Answers
5
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How to use GROUP_CONCAT in a CONCAT in MySQL
If I have a table with the following data in MySQL:
7 Answers
7
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Does Foreign Key improve query performance?
Suppose I have 2 tables, Products and ProductCategories. Both tables have relationship on CategoryId. And this is the query.
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jQuery: count number of rows in a table
How do I count the number of tr elements within a table using jQuery?
11 Answers
11
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Access Denied for User 'root'@'localhost' (using password: YES) - No Privileges?
...ot password, we'll going to forcefully INSERT a record into the mysql.user table
In the init file, use this instead
INSERT INTO mysql.user (Host, User, Password) VALUES ('%', 'root', password('YOURPASSWORD'));
GRANT ALL ON *.* TO 'root'@'%' WITH GRANT OPTION;
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Is an index needed for a primary key in SQLite?
When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all t...
How to replace a string in a SQL Server Table Column
I have a table ( SQL Sever ) which references paths ( UNC or otherwise), but now the path is going to change.
10 Answers
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