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How to get multiple selected values of select box in php?
I have a html form which has a select list box from which you can select multiple values because its multiple property is set to multiple. Consider form method is 'GET'. The html code for the form is as follows:
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What is the simplest SQL Query to find the second largest value?
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SELECT MAX( col )
FROM table
WHERE col < ( SELECT MAX( col )
FROM table )
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When to use Common Table Expression (CTE)
...ing well? Can someone give me a simple example of limitations with regular select, derived or temp table queries to make the case of CTE? Any simple examples would be highly appreciated.
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Can you have if-then-else logic in SQL? [duplicate]
I need to do select data from a table based on some kind of priority like so:
7 Answers
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How to select rows with no matching entry in another table?
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Here's a simple query:
SELECT t1.ID
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
WHERE t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
Select row with most recent date per user
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Query:
SQLFIDDLEExample
SELECT t1.*
FROM lms_attendance t1
WHERE t1.time = (SELECT MAX(t2.time)
FROM lms_attendance t2
WHERE t2.user = t1.user)
Result:
| ID | USER | TIME | IO |
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SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
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How do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...
SQL - find records from one table which don't exist in another
...shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alternatively (thanks to Alterlife)
SELECT *
FROM Call
WHERE NOT EXISTS
(SELECT *
FROM Phone_book
WHERE Phone_book.phon...
Select multiple images from android gallery
... am trying to achieve is opening the Gallery in Android and let the user select multiple images . Now this question has been asked frequently but i'm not satisfied with the answers. Mainly because i found something interesting in de docs in my IDE (i come back on this later) and thereby i don't...