大约有 40,000 项符合查询结果（耗时：0.0310秒） [XML]
Dropping Unique constraint from MySQL table
How can I drop the "Unique Key Constraint" on a column of a MySQL table using phpMyAdmin?
10 Answers
...
What MySQL data type should be used for Latitude/Longitude with 8 decimal places?
...
DECIMAL is the MySQL data-type for exact arithmetic. Unlike FLOAT its precision is fixed for any size of number, so by using it instead of FLOAT you might avoid precision errors when doing some calculations. If you were just storing and ret...
MySQL remove all whitespaces from the entire column
...UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\n', '')
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace
To remove first and last space(s) of column :
UPDATE `table` SET `col_name` = TRIM(`col_name`)
http://dev.mysql.com/doc/refman/5.0/en/string-functions.htm...
What's the difference between VARCHAR and CHAR?
What's the difference between VARCHAR and CHAR in MySQL?
14 Answers
14
...
Creation timestamp and last update timestamp with Hibernate and MySQL
...
I would do this using a MySQL trigger so that even if the full entity is not saved or is modified by any external application or manual query, it'll still update these fields.
– Webnet
Jul 25 '13 at 12:09
...
MyISAM versus InnoDB [closed]
...o
But, frequent reading, almost no writing, use MyISAM
Full-text search in MySQL <= 5.5, use MyISAM
share
|
improve this answer
|
follow
|
...
How to log PostgreSQL queries?
... that mean PostgreSQL can't enable logging unless I restart the server? In MySQL, it is as simple as "SET GLOBAL general_log = 'ON';"
– Antony
Dec 7 '11 at 22:41
7
...
MySQL Creating tables with Foreign Keys giving errno: 150
I am trying to create a table in MySQL with two foreign keys, which reference the primary keys in 2 other tables, but I am getting an errno: 150 error and it will not create the table.
...
Difference between Key, Primary Key, Unique Key and Index in MySQL
...
KEY and INDEX are synonyms in MySQL. They mean the same thing. In databases you would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called...
Can\'t connect to local MySQL server through socket \'/tmp/mysql.sock\...
Can't connect to local MySQL server through socket '/tmp/mysql.sock'ln -s var lib mysql mysql.sock tmp mysql.sock 建个link即可，不解释。
ln -s /var/lib/mysql/mysql.sock /tmp/mysql.sock
建个link即可，不解释。MySQL mysql.sock