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‎README.md‎

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# MySQL
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## Getting started
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- http://www.sqlteaching.com/
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- https://www.codecademy.com/learn/learn-sql
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### Related tutorials
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- [MySQL-CLI](https://www.youtube.com/playlist?list=PLfdtiltiRHWEw4-kRrh1ZZy_3OcQxTn7P)
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- [Analyzing Business Metrics](https://www.codecademy.com/learn/sql-analyzing-business-metrics)
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- [SQL joins infografic](https://www.codeproject.com/Articles/33052/Visual-Representation-of-SQL-Joins)
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## Tools
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- [TablePlus](https://tableplus.io/)
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- [DataGrip](https://www.jetbrains.com/datagrip/)
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- [Sequel Pro](http://www.sequelpro.com/) (abandoned)
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## Commands
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Access monitor: `mysql -u [username] -p;` (will prompt for password)
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Show all databases: `show databases;`
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Access database: `mysql -u [username] -p [database]` (will prompt for password)
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Create new database: `create database [database];`
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Select database: `use [database];`
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Determine what database is in use: `select database();`
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Show all tables: `show tables;`
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Show table structure: `describe [table];`
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List all indexes on a table: `show index from [table];`
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Create new table with columns: `CREATE TABLE [table] ([column] VARCHAR(120), [another-column] DATETIME);`
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Adding a column: `ALTER TABLE [table] ADD COLUMN [column] VARCHAR(120);`
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Adding a column with an unique, auto-incrementing ID: `ALTER TABLE [table] ADD COLUMN [column] int NOT NULL AUTO_INCREMENT PRIMARY KEY;`
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Inserting a record: `INSERT INTO [table] ([column], [column]) VALUES ('[value]', [value]');`
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MySQL function for datetime input: `NOW()`
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Selecting records: `SELECT * FROM [table];`
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Explain records: `EXPLAIN SELECT * FROM [table];`
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Selecting parts of records: `SELECT [column], [another-column] FROM [table];`
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Counting records: `SELECT COUNT([column]) FROM [table];`
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Counting and selecting grouped records: `SELECT *, (SELECT COUNT([column]) FROM [table]) AS count FROM [table] GROUP BY [column];`
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Selecting specific records: `SELECT * FROM [table] WHERE [column] = [value];` (Selectors: `<`, `>`, `!=`; combine multiple selectors with `AND`, `OR`)
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Select records containing `[value]`: `SELECT * FROM [table] WHERE [column] LIKE '%[value]%';`
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Select records starting with `[value]`: `SELECT * FROM [table] WHERE [column] LIKE '[value]%';`
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Select records starting with `val` and ending with `ue`: `SELECT * FROM [table] WHERE [column] LIKE '[val_ue]';`
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Select a range: `SELECT * FROM [table] WHERE [column] BETWEEN [value1] and [value2];`
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Select with custom order and only limit: `SELECT * FROM [table] WHERE [column] ORDER BY [column] ASC LIMIT [value];` (Order: `DESC`, `ASC`)
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Updating records: `UPDATE [table] SET [column] = '[updated-value]' WHERE [column] = [value];`
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Deleting records: `DELETE FROM [table] WHERE [column] = [value];`
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Delete *all records* from a table (without dropping the table itself): `DELETE FROM [table];`
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(This also resets the incrementing counter for auto generated columns like an id column.)
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Delete all records in a table: `truncate table [table];`
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Removing table columns: `ALTER TABLE [table] DROP COLUMN [column];`
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Deleting tables: `DROP TABLE [table];`
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Deleting databases: `DROP DATABASE [database];`
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Custom column output names: `SELECT [column] AS [custom-column] FROM [table];`
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Export a database dump (more info [here](http://stackoverflow.com/a/21091197/1815847)): `mysqldump -u [username] -p [database] > db_backup.sql`
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Use `--lock-tables=false` option for locked tables (more info [here](http://stackoverflow.com/a/104628/1815847)).
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Import a database dump (more info [here](http://stackoverflow.com/a/21091197/1815847)): `mysql -u [username] -p -h localhost [database] < db_backup.sql`
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Logout: `exit;`
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## Aggregate functions
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Select but without duplicates: `SELECT distinct name, email, acception FROM owners WHERE acception = 1 AND date >= 2015年01月01日 00:00:00`
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Calculate total number of records: `SELECT SUM([column]) FROM [table];`
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Count total number of `[column]` and group by `[category-column]`: `SELECT [category-column], SUM([column]) FROM [table] GROUP BY [category-column];`
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Get largest value in `[column]`: `SELECT MAX([column]) FROM [table];`
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Get smallest value: `SELECT MIN([column]) FROM [table];`
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Get average value: `SELECT AVG([column]) FROM [table];`
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Get rounded average value and group by `[category-column]`: `SELECT [category-column], ROUND(AVG([column]), 2) FROM [table] GROUP BY [category-column];`
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## Multiple tables
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Select from multiple tables: `SELECT [table1].[column], [table1].[another-column], [table2].[column] FROM [table1], [table2];`
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Combine rows from different tables: `SELECT * FROM [table1] INNER JOIN [table2] ON [table1].[column] = [table2].[column];`
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Combine rows from different tables but do not require the join condition: `SELECT * FROM [table1] LEFT OUTER JOIN [table2] ON [table1].[column] = [table2].[column];` (The left table is the first table that appears in the statement.)
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Rename column or table using an _alias_: `SELECT [table1].[column] AS '[value]', [table2].[column] AS '[value]' FROM [table1], [table2];`
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## Users functions
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List all users: `SELECT User,Host FROM mysql.user;`
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Create new user: `CREATE USER 'username'@'localhost' IDENTIFIED BY 'password';`
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Grant `ALL` access to user for `*` tables: `GRANT ALL ON database.* TO 'user'@'localhost';`
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## Find out the IP Address of the Mysql Host
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`SHOW VARIABLES WHERE Variable_name = 'hostname';` ([source](http://serverfault.com/a/129646))

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