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When should I use Kruskal as opposed to Prim (and vice versa)?
...c.
If you implement both Kruskal and Prim, in their optimal form : with a union find and a finbonacci heap respectively, then you will note how Kruskal is easy to implement compared to Prim.
Prim is harder with a fibonacci heap mainly because you have to maintain a book-keeping table to record the...
How do you debug MySQL stored procedures?
...ariable at a given point in the script, but is there a better way to debug MySQL stored procedures?
16 Answers
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Storing Data in MySQL as JSON
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CouchDB and MySQL are two very different beasts. JSON is the native way to store stuff in CouchDB. In MySQL, the best you could do is store JSON data as text in a single field. This would entirely defeat the purpose of storing it in an R...
Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
... to historical, code legacy reasons, has been lifted in recent versions of MySQL:
Changes in MySQL 5.6.5 (2012-04-10, Milestone 8)
Previously, at most one TIMESTAMP column per table could be
automatically initialized or updated to the current date and time.
This restriction has been li...
Increment value in mysql update query
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You could also just do this:
mysql_query("
UPDATE member_profile
SET points = points + 1
WHERE user_id = '".$userid."'
");
share
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improve...
MySQL check if a table exists without throwing an exception
What is the best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
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insert multiple rows via a php array into mysql
I'm passing a large dataset into a MySQL table via PHP using insert commands and I'm wondering if its possible to insert approximately 1000 rows at a time via a query other than appending each value on the end of a mile long string and then executing it. I am using the CodeIgniter framework so its f...
Why does Git treat this text file as a binary file?
...a correct information. I was trying to control diffs to an extremely large MySQL Dump (.sql file), but git treats it as a binary file, even if it has only ASCII/UTF8 data on it. The reason, is that lines are super-long (insert values (one),(two),(three),(...),(3 million...);. Strangely, for every co...
MySQL error: key specification without a key length
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The error happens because MySQL can index only the first N chars of a BLOB or TEXT column. So The error mainly happens when there is a field/column type of TEXT or BLOB or those belong to TEXT or BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINY...
Create boolean column in MySQL with false as default value?
I want to create a table in MySQL with a boolean column whose default value is false . But it's accepting NULL as default...
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