SQL

Sat, 14 Jan 2023 00:00:00 +0000

JOIN

inner join, left join, right join, full outer join

PostgreSQL

Wed, 29 Apr 2015 23:01:00 +0000

Installation

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`1`	`brew install postgres`

Start

To have launchd start postgresql now and restart at login:

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`1`	`brew services start postgresql`

Or, if you don’t want/need a background service you can just run:

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`1`	`pg_ctl -D /usr/local/var/postgres start`

in Debian

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`1`	`sudo /etc/init.d/postgresql start`

JDBC Connector

JDBC connector

MySQL

Tue, 28 Apr 2015 23:01:00 +0000

References

Upgrading to MySQL from 5.x to 8.x

Upgrading to MySQL Connector/J 8.0

Dropping database, user

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DROP DATABASE IF EXISTS dbname;
DROP USER dbname@localhost;

Creating database, user and privileges

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CREATE DATABASE dbname CHARACTER SET utf8 COLLATE utf8_general_ci;
CREATE USER dbname@localhost IDENTIFIED BY 'P@ssword1';
GRANT ALL PRIVILEGES ON dbname.* TO dbname@localhost;
FLUSH PRIVILEGES;

Setting user password

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SET PASSWORD FOR 'dbname'@'localhost' = PASSWORD('P@ssword1');
FLUSH PRIVILEGES;

Resetting a forgotten root password

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/etc/init.d/mysql stop
/usr/bin/mysqld_safe --skip-grant-tables &amp;
mysql --user=root mysql

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mysql> update user set Password=PASSWORD('P@ssword1') WHERE User='root';
mysql> flush privileges;
mysql> exit

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`1`	`/etc/init.d/mysql start`

Group output of SHOW COLUMNS into comma-delimited list

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select group_concat(column_name order by ordinal_position)
from information_schema.columns
where table_schema = 'database_name' and table_name = 'table_name';

output

Relational Database on ARI Systems

SQL

JOIN

PostgreSQL

Installation

Start

JDBC Connector

MySQL

References

Upgrading to MySQL from 5.x to 8.x

Dropping database, user

Creating database, user and privileges

Setting user password

Resetting a forgotten root password

Group output of SHOW COLUMNS into comma-delimited list