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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 ...
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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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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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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What is a good reason to use SQL views?
...one of the previous answers seem to have mentioned is easier deployment of table structure changes.
Say, you wish to retire a table (T_OLD) containing data for active users, and instead use a new table with similar data (named T_NEW) but one that has data for both active and inactive users, with on...
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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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...
SQL Server Linked Server Example Query
...at should probably be:
<server>.<database>.<schema>.<table>
For example:
DatabaseServer1.db1.dbo.table1
Update: I know this is an old question and the answer I have is correct; however, I think any one else stumbling upon this should know a few things.
Namely, when que...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
How do I modify the owner of all tables in a PostgreSQL database?
20 Answers
20
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