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Does MySQL foreign_key_checks affect the entire database?
When I execute this command in MySQL:
6 Answers
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Importance of varchar length in MySQL table
I have a MySQL table where rows are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessar...
How does MySQL process ORDER BY and LIMIT in a query?
... @Green, you're mistaken. Read this for the explanation: dev.mysql.com/doc/refman/5.7/en/limit-optimization.html When the ORDER BY column is indexed, it may return records in a different order than without the LIMIT, when there are more than 1 records with the same value in that column...
Error 1046 No database Selected, how to resolve?
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You need to tell MySQL which database to use:
USE database_name;
before you create a table.
In case the database does not exist, you need to create it as:
CREATE DATABASE database_name;
followed by:
USE database_name;
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How to get the sizes of the tables of a MySQL database?
I can run this query to get the sizes of all tables in a MySQL database:
16 Answers
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Is there a MySQL command to convert a string to lowercase?
I have a MySQL database of keywords that are presently mixed-case. However, I want to convert them all to lowercase. Is there an easy command to do this, either using MySQL or MySQL and PHP?
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MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
...ll, both syntaxes are equivalent. The first is SQL standard, the second is MySQL's extension.
So they should be exactly equivalent performance wise.
http://dev.mysql.com/doc/refman/5.6/en/insert.html says:
INSERT inserts new rows into an existing table. The INSERT ... VALUES and INSERT ... SET...
How can you determine how much disk space a particular MySQL table is taking up?
Is there a quick way to determine how much disk space a particular MySQL table is taking up? The table may be MyISAM or Innodb.
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How to Get True Size of MySQL Database?
I would like to know how much space does my MySQL database use, in order to select a web host.
I found the command SHOW TABLE STATUS LIKE 'table_name' so when I do the query, I get something like this:
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Convert JS date time to MySQL datetime
Does anyone know how to convert JS dateTime to MySQL datetime? Also is there a way to add a specific number of minutes to JS datetime and then pass it to MySQL datetime?
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