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How do I find duplicate values in a table in Oracle?
...then use a HAVING clause to find values that appear greater than one time.
SELECT column_name, COUNT(column_name)
FROM table_name
GROUP BY column_name
HAVING COUNT(column_name) > 1;
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How to restore to a different database in sql server?
...restore. Kill all running processes by right clicking on each process and selecting "kill process".
Right click on the database you wish to restore, and select Tasks-->Restore-->From Database.
Select the "From Device:" radio button.
Select ... and choose the backup file of the other database ...
select count(*) from table of mysql in php
...s keyword in order to call it from mysql_fetch_assoc
$result=mysql_query("SELECT count(*) as total from Students");
$data=mysql_fetch_assoc($result);
echo $data['total'];
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Fastest check if row exists in PostgreSQL
...
Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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MySQL “WITH” clause
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You might be interested in somethinkg like this:
select * from (
select * from table
) as Subquery
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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...
How can I select every other line with multiple cursors in Sublime Text?
In Sublime Text 2, is it possible to instantly select every other (or odd/even) line and place multiple cursors on those lines?
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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
How can I convert comma separated string into a List
...
Here is one way of doing it:
List<int> TagIds = tags.Split(',').Select(int.Parse).ToList();
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List all sequences in a Postgres db 8.1 with SQL
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The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the following query:...