Mysql: Difference between revisions

From Wiki
Jump to navigation Jump to search
Line 48: Line 48:
== Backing up and restoring a database ==
== Backing up and restoring a database ==
To back up the database "bookstore" to a file sq5.sql:
To back up the database "bookstore" to a file sq5.sql:
<pre>
mysqldump --opt -pXXXXX bookstore > bookstore.sql
mysqldump --opt -pXXXXX bookstore > bookstore.sql
 
</pre>
To restore a database from backup (overwrites any existing):
To restore a database from backup (overwrites any existing):
<pre>
mysql -u root -p bookstore < bookstore.sql
mysql -u root -p bookstore < bookstore.sql
</pre>


== Searching on three-character words ==
== Searching on three-character words ==

Revision as of 18:38, 19 November 2014

Ubuntu setup

Root password should already be created.

apt-get install mysql-server

Log in as root to mysql database

mysql -u root -p mysql
select * from user;
delete from user where host = 'myserver';
create user barney@localhost identified by 'xxxxxxxx';
create database bookstore;
grant all privileges on bookstore.* to barney@localhost;  # regular account
grant select on bookstore.* to barney@localhost;          # read-only account
grant file on *.* to barney@localhost;                    # write output to files
flush privileges;

File I/O

You should have already granted "file" privileges to user:

grant file on *.* to barney@localhost;
flush privileges;

To execute SQL commands in a text file (from the command line):

mysql -u barney -p bookstore < mycommands.sql

To execute SQL commands in a text file (from the mysql prompt):

mysql> use bookstore;
mysql> source /home/barney/sql/mycommands.sql;

To read data out to a file (NOTE: The mysql user must have write permissions on the intended output directory):

select ... into outfile "/home/barney/sql/goodbooks.txt";

To load a file into a table:

load data local infile "/home/barney/sql/goodbooks.txt" into table books;

Backing up and restoring a database

To back up the database "bookstore" to a file sq5.sql:

mysqldump --opt -pXXXXX bookstore > bookstore.sql

To restore a database from backup (overwrites any existing):

mysql -u root -p bookstore < bookstore.sql

Searching on three-character words

  • Edit /etc/mysql/my.cnf to add this line to the [mysqld] section:
ft_min_word_len=3
  • Restart mysql.
  • For each table you are doing a fulltext search on, run this command:
repair table <table_name> quick;

Create database/table example

drop database if exists edapt_quiz;
create database edapt_quiz;
use edapt_quiz;

drop table if exists quizzes;
create table quizzes (
    id              int unsigned not null auto_increment,
    name            varchar(64) not null,
    primary key (id)
) engine=innodb;
insert into quizzes (name) values ('Prodromal Questionnaire – Brief Version');

drop table if exists questions;
create table questions (
    id              int unsigned not null auto_increment,
    quiz_id         int unsigned not null,
    sort_order      smallint,
    text            text,
    primary key (id),
    foreign key (quiz_id) references quizzes(id)
) engine=innodb;