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MySQL combine two columns into one column
...does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two ways to add a space:
select concat(column1, ' ', column2)
select concat_ws(' ', column1, column2)
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MySQL: Selecting multiple fields into multiple variables in a stored procedure
Can I SELECT multiple columns into multiple variables within the same select query in MySQL?
3 Answers
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Linq: What is the difference between Select and Where
The Select and Where methods are available in Linq. What should every developer know about these two methods? For example: when to use one over the other, any advantages of using one over the other, etc.
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How to use Oracle ORDER BY and ROWNUM correctly?
...n Oracle.
If you want a version that works in both servers, you can use:
select ril.*
from (select ril.*, row_number() over (order by t_stamp desc) as seqnum
from raceway_input_labo ril
) ril
where seqnum = 1
The outer * will return "1" in the last column. You would need to list the ...
How to submit form on change of dropdown list?
I am creating a page in JSP where I have a dropdown list and once the user selects a value he has to click on the go button and then the value is sent to the Servlet.
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How do I get a list of column names from a psycopg2 cursor?
I would like a general way to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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LEFT JOIN only first row
...rtist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = f.feed_id
) a
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SQL Server insert if not exists best practice
...sert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName)
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PHP PDO returning single row
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$dbh = new PDO(" --- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
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Are PDO prepared statements sufficient to prevent SQL injection?
....
$pdo->query('SET NAMES gbk');
$var = "\xbf\x27 OR 1=1 /*";
$query = 'SELECT * FROM test WHERE name = ? LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute(array($var));
In certain circumstances, that will return more than 1 row. Let's dissect what's going on here:
Selecting a Cha...