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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 to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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Remove Primary Key in MySQL
... following table schema which maps user_customers to permissions on a live MySQL database:
12 Answers
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Which is faster: multiple single INSERTs or one multiple-row INSERT?
I am trying to optimize one part of my code that inserts data into MySQL. Should I chain INSERTs to make one huge multiple-row INSERT or are multiple separate INSERTs faster?
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clang error: unknown argument: '-mno-fused-madd' (python package installation failure)
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If you install as root you need to set the flags for the root user.
– ErikAndren
Mar 18 '14 at 6:29
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Prevent direct access to a php include file
...direct access to files is to place them outside of the web-server document root (usually, one level above). You can still include them, but there is no possibility of someone accessing them through an http request.
I usually go all the way, and place all of my PHP files outside of the document root...
How to select the last record of a table in SQL?
...s something like
Sql Server
SELECT TOP 1 * FROM Table ORDER BY ID DESC
MySql
SELECT * FROM Table ORDER BY ID DESC LIMIT 1
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How can I see the specific value of the sql_mode?
There are some sql_mode values in MySQL:
2 Answers
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Can I use a function for a default value in MySql?
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Sad that MySQL has been around for as long as it has but you can't implement a default UUID for a column without a trigger. The reason for this is embedded in the 1980's technology that apparently still exists in the MySQL base code (...
How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...e->timestamp('created_at')->useCurrent();
Back to the question, on MySQL you could also use the ON UPDATE clause through DB::raw():
$table->timestamp('updated_at')->default(DB::raw('CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP'));
Gotchas
MySQL
Starting with MySQL 5.7, 0000-00-00...