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PostgreSQL naming conventions
Where can I find a detailed manual about PostgreSQL naming conventions? (table names vs. camel case, sequences, primary keys, constraints, indexes, etc...)
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What is the difference between HAVING and WHERE in SQL?
..., CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than ...
Get top 1 row of each group
I have a table which I want to get the latest entry for each group. Here's the table:
20 Answers
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How do I create a PDO parameterized query with a LIKE statement?
...t out right after I posted:
$query = $database->prepare('SELECT * FROM table WHERE column LIKE ?');
$query->execute(array('value%'));
while ($results = $query->fetch())
{
echo $results['column'];
}
share
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Update multiple columns in SQL
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Try this:
UPDATE table1
SET a = t2.a, b = t2.b, .......
FROM table2 t2
WHERE table1.id = t2.id
That should work in most SQL dialects, excluding Oracle.
And yes - it's a lot of typing - it's the way SQL does this.
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Create boolean column in MySQL with false as default value?
I want to create a table in MySQL with a boolean column whose default value is false . But it's accepting NULL as default...
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How to persist a property of type List in JPA?
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@Please_Dont_Bully_Me_SO_Lords It is less suitable for that use case since your data will be in the database as "foo;bar;foobar". If you want to query for the data then probably an ElementCollection + JoinTable is the way to go for your situation.
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FIND_IN_SET() vs IN()
I have 2 tables in my database. One is for orders, and one is for companies.
6 Answers
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MySQL high CPU usage [closed]
... time, and use that to make sure you don't have any queries locking up key tables for too long.
Some other things you can check would be to run the following query while the CPU load is high:
SHOW PROCESSLIST;
This will show you any queries that are currently running or in the queue to run, what...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
I want to use Oracle SQL Developer to generate an ER diagram for my DB tables but I am new to Oracle and this tool.
8 Answe...