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MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
...B and you only select indexed fields (and things are not too complex) than MySQL will resolve your query using only the indexes, speeding things way up.
General solution for 90% of your IN (select queries
Use this code
SELECT * FROM sometable a WHERE EXISTS (
SELECT 1 FROM sometable b
WHERE...
Call to undefined method mysqli_stmt::get_result
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Please read the user notes for this method:
http://php.net/manual/en/mysqli-stmt.get-result.php
It requires the mysqlnd driver... if it isn't installed on your webspace you will have to work with BIND_RESULT & FETCH!
https://secure.php.net/manual/en/mysqli-stmt.bind-result.php
https://s...
How to store arrays in MySQL?
I have two tables in MySQL. Table Person has the following columns:
7 Answers
7
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Random record in ActiveRecord
...selected entries. (Be aware that it's RANDOM() in PostgreSQL and RAND() in MySQL ... not as portable as you may want it to be.)
– Florian Pilz
Jun 16 '11 at 13:17
3
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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
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It depends. See the MySQL Performance Blog post on this subject: To SQL_CALC_FOUND_ROWS or not to SQL_CALC_FOUND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to...
How do you list all triggers in a MySQL database?
What is the command to list all triggers in a MySQL database?
4 Answers
4
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What is the difference between tree depth and height?
... number of nodes and in other number of edges on the shortest path between root and concrete node.
Which is which?
7 Answ...
In Java, what is the best way to determine the size of an object?
... Pattern.normalizedPattern (object)
44 4 Node Pattern.root (object)
48 4 Node Pattern.matchRoot (object)
52 4 int[] Pattern.buffer null
56 4 Map Pattern.namedGroups null
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MySQL: Invalid use of group function
I am using MySQL. Here is my schema:
2 Answers
2
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Querying data by joining two tables in two database on different servers
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is it possible with php-mysql ..if yes then can you please suggest me a way how can i grow with that option?
– Jhanvi
Sep 26 '12 at 8:47
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