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MySQL Query GROUP BY day / month / year
... for added clarity in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
...
what is the difference between GROUP BY and ORDER BY in sql
... SUM, COUNT, AVG, etc).
TABLE:
ID NAME
1 Peter
2 John
3 Greg
4 Peter
SELECT *
FROM TABLE
ORDER BY NAME
=
3 Greg
2 John
1 Peter
4 Peter
SELECT Count(ID), NAME
FROM TABLE
GROUP BY NAME
=
1 Greg
1 John
2 Peter
SELECT NAME
FROM TABLE
GROUP BY NAME
HAVING Count(ID) > 1
=
Peter
...
Count table rows
...
SELECT COUNT(*) FROM fooTable;
will count the number of rows in the table.
See the reference manual.
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How to set caret(cursor) position in contenteditable element (div)?
...
In most browsers, you need the Range and Selection objects. You specify each of the selection boundaries as a node and an offset within that node. For example, to set the caret to the fifth character of the second line of text, you'd do the following:
function s...
Fluent and Query Expression — Is there any benefit(s) of one over other?
...me in fullNames
from name in fullName.Split()
orderby fullName, name
select name + " came from " + fullName;
Now compare this to the same thing in method syntax:
var query = fullNames
.SelectMany (fName => fName.Split().Select (name => new { name, fName } ))
.OrderBy (x => x.fN...
Resetting a multi-stage form with jQuery
...n, :submit, :reset, :hidden')
.val('')
.removeAttr('checked')
.removeAttr('selected');
Which might work for a lot of cases, including for the OP, but as pointed out in the comments and in other answers, will clear radio/checkbox elements from any value attributes.
A more correct answer (but not per...
PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
Firefox ignores option selected=“selected”
If you change a dropdown and refresh the page, Firefox seems to ignore the selected attribute.
20 Answers
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MySQL: Quick breakdown of the types of joins [duplicate]
...es
END EDIT
In a nutshell, the comma separated example you gave of
SELECT * FROM a, b WHERE b.id = a.beeId AND ...
is selecting every record from tables a and b with the commas separating the tables, this can be used also in columns like
SELECT a.beeName,b.* FROM a, b WHERE b.id = a.beeId...