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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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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 ...
Counting the number of option tags in a select tag in jQuery
How do I count the number of <option> s in a <select> DOM element using jQuery?
8 Answers
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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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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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PHP PDO returning single row
...
$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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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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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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python list in sql query as parameter
...I paramstyle.
placeholders= ', '.join(placeholder for unused in l)
query= 'SELECT name FROM students WHERE id IN (%s)' % placeholders
cursor.execute(query, l)
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