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How to declare variable and use it in the same Oracle SQL script?
...; exec :name := 'SALES'
PL/SQL procedure successfully completed.
SQL> select * from dept
2 where dname = :name
3 /
DEPTNO DNAME LOC
---------- -------------- -------------
30 SALES CHICAGO
SQL>
A VAR is particularly useful when we want to call a stored...
Python: How would you save a simple settings/config file?
... reasons to use a different format.
Write a file like so:
# python 2.x
# from ConfigParser import SafeConfigParser
# config = SafeConfigParser()
# python 3.x
from configparser import ConfigParser
config = ConfigParser()
config.read('config.ini')
config.add_section('main')
config.set('main', 'key...
How does a language expand itself? [closed]
...
A computer is like an onion, it has many many layers, from the inner core of pure hardware to the outermost application layer. Each layer exposes parts of itself to the next outer layer, so that the outer layer may use some of the inner layers functionality.
In the case of e.g....
MySQL - Get row number on select
Can I run a select statement and get the row number if the items are sorted?
5 Answers
...
How do you use the “WITH” clause in MySQL?
...s mentioned, you provided a poor example - there's no need to perform a subselect if you aren't altering the output of the columns in any way:
SELECT *
FROM ARTICLE t
JOIN USERINFO ui ON ui.user_userid = t.article_ownerid
JOIN CATEGORY c ON c.catid = t.article_categoryid
WHERE t....
How to select a drop-down menu value with Selenium using Python?
I need to select an element from a drop-down menu.
13 Answers
13
...
You can't specify target table for update in FROM clause
...llow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't reference that table in an inner query (you can however reference a field from that outer table...)
Th...
What is the difference between float and double?
...le gives 9.000000000000000066 on Mac), but all floating point types suffer from round-off errors, so if precision is very important (e.g. money processing) you should use int or a fraction class.
Furthermore, don't use += to sum lots of floating point numbers, as the errors accumulate quickly. If y...
Simple way to transpose columns and rows in SQL?
...3, 5),
('Blue', 2, 2, 9, 1);
Union All, Aggregate and CASE Version:
select name,
sum(case when color = 'Red' then value else 0 end) Red,
sum(case when color = 'Green' then value else 0 end) Green,
sum(case when color = 'Blue' then value else 0 end) Blue
from
(
select color, Paul value...
How do I limit the number of rows returned by an Oracle query after ordering?
...Oracle in this answer).
To answer the original question, here's the query:
SELECT *
FROM sometable
ORDER BY name
OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY;
(For earlier Oracle versions, please refer to other answers in this question)
Examples:
Following examples were quoted from linked page, in th...