How to do a MySQL recursive query?

Let’s learn how to do a MySQL recursive query. The most accurate or helpful solution is served by Stack Overflow.

There are ten answers to this question.

Best solution

how to work with recursive query in MySql?

WITH RECURSIVE transitive_closure(a, b, distance, path_string) AS ( SELECT a, b, 1 AS distance, a || '.' || b || '.' AS path_string, b AS direct_connection FROM edges2 WHERE a = 1 -- set the starting node UNION ALL SELECT tc.a, e.b, tc.distance + 1, tc.path_string || e.b || '.' AS path_string, tc.direct_connection FROM edges2 AS e JOIN transitive_closure AS tc ON e.a = tc.b WHERE tc.path_string NOT LIKE '%' || e.b || '.%' AND tc.distance < 3 ) SELECT * FROM transitive_closure --WHERE b=3 -...

Answer:

The WITH RECURSIVE statement/method is applicable in PostgreSQL and Sybase (and maybe a few more, I...

Read more

Maulik patel at Stack Overflow Mark as irrelevant Undo

Other solutions

How to seperate results in mysql $query?

$k = $_GET ['k']; $terms = explode(" ", $k); $query = "SELECT * FROM mattsdbone WHERE "; foreach ($terms as $each){ $i++; if ($i == 1) $query .= "category_name LIKE '%$each%' "; else $query .= "OR category_name LIKE...

Answer:

Add error_reporting(E_ALL), as the first line of your php file, just after the <?php That will show...

Read more

Joe at Yahoo! Answers Mark as irrelevant Undo

How to test a query's syntax using MySQL without executing the query

I want to be able to pass any query to MySQL, have MySQL check whether the query's syntax is valid, including whether non-existing tables or columns have been referenced, and return an error if something is wrong, WITHOUT actually executing the query...

Answer:

Hi, I've been working with MySQL for almost 10 years, and never heard of such a setting. I checked...

Read more

vladkornea-ga at Google Answers Mark as irrelevant Undo

How to do this mysql query on 2 tables?

I have 2 tables, one named ARTICLE and one named COMMENTS. Say ARTICLE table contains … -ID - article And COMMENT table contains… -ID -article_id (which will be related to “ ID” in the articles table) -comment I have a simple...

Answer:

SELECT a.id AS "Article ID", COUNT(*) AS "Number of Comments" FROM article a JOIN...

Read more

TheMadPr... at Yahoo! Answers Mark as irrelevant Undo

WordPress Plugin Development: How can I set a MySQL query to specify the options table using a user defined prefix?

I have the following line in my plugin to remove transients from the database option table. $wpdb->query( "DELETE FROM `wp_options` WHERE `option_name` LIKE ('_transient%_feed_%')" ); However, it won't work with sites which set a prefix...

Answer:

Use the global wordpress variable $table_prefix in your query: $wpdb->query( "DELETE FROM ...

Read more

Nicholas Pickering at Quora Mark as irrelevant Undo

How do I reduce MySQL query execution time from 90s to less than 5s or even ONE?

I am using MySQL database. When I execute a query which the main table(20 thousands of rows) is joined with the other 5 tables, it takes 90 seconds to return me the result. I then added indices into each of the criteria(where clause). Then the execution...

Answer:

Optimizing MySQL queries is a fairly straightforward process. To solve your problem would require a...

Read more

Juan Cristián Vera Huneeus at Quora Mark as irrelevant Undo

How do I join multiple tables in a mysql query?

I already know how to join two tables or even three, but my situation is a little different....I have a table of mobile homes for sale....I have a second table of the parks those homes are in. I have a third table of bank repossesions that exist in mobile...

Answer:

Hi, Here I am assuming that table PARK with mobile homes is related to table MOBILEHOME. So I have joined...

Read more

BA at Yahoo! Answers Mark as irrelevant Undo

How to INSERT a SELECT query in MYSQL?

INSERT INTO Vendor (VName, VPhone, VLoc) VALUES ('Mike Douglas', '260-555-5555', 'Denver, CO)"; The Vendor table also has a field for CarID. There is a Car Table that has the following row: CarID: 89 | Make: Pontiac | Model: GrandAm | Miles: 87...

Answer:

http://www.google.com/search?q=insert+in… has links to some examples.

Read more

Chris S at Yahoo! Answers Mark as irrelevant Undo

How can I do query level prioritization on MySQL when using InnoDB?

As of now I have a single DB setup (both reads and writes are done on this). Now I have an hourly cron which do heavy reads and writes on this and then I have users using the system. I will like to make sure that user queries are given precedence by...

Answer:

Another possible solution: Setup Master to Master replication, direct cron to 1 master and users to...

Read more

Manoj Murumkar at Quora Mark as irrelevant Undo

How can I solve the "Error Code: 2013 Lost connection to MySQL server during query 600.135 sec" error message?

(Windows 7 64-bit Ultimate, MySQL Workbench 5.2.47 CE) The following figure shows 6.5 sec instead of the usual ~600 seconds as it was fastest to illustrate:

Answer:

http://bugs.mysql.com/bug.php?id...: Go to Preferences -> SQL Editor and set to a bigger value this...

Read more

Franck Dernoncourt at Quora Mark as irrelevant Undo

Related Q & A:

Just Added Q & A:

Find solution

For every problem there is a solution! Proved by Solucija.

  • Got an issue and looking for advice?

  • Ask Solucija to search every corner of the Web for help.

  • Get workable solutions and helpful tips in a moment.

Just ask Solucija about an issue you face and immediately get a list of ready solutions, answers and tips from other Internet users. We always provide the most suitable and complete answer to your question at the top, along with a few good alternatives below.