For clarity, they are shown in uppercase. The SQL keywords and commands are NOT case-sensitive. A table is made up of columns (or fields) and rows ( records). Each database consists of one or more tables. SHOW WARNINGS - Show the warnings of the previous statement An Example for the Beginners (But NOT for the dummies)Ī MySQL database server contains many databases (or schemas). , columnNValue) - Insert on selected Columns VALUES ( column1Value, column2Value.) - Insert on all Columns SHOW CREATE TABLE tableName - Show the CREATE TABLE statement for this tableName - Row-Level Modify a table, e.g., ADD COLUMN and DROP COLUMNĪLTER TABLE tableName ADD columnDefinitionĪLTER TABLE tableName ADD FOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) ALTER TABLE tableName DROP FOREIGN KEY constraintName SHOW TABLES - Show all the tables in the default databaseĭESCRIBE|DESC tableName - Describe the details for a tableĪLTER TABLE tableName. įOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) SHOW CREATE DATABASE databaseName - Show the CREATE DATABASE statement - Table-LevelĬolumnName columnType columnAttribute. SELECT DATABASE() - Show the default database USE databaseName - Set the default (current) database SHOW DATABASES - Show all the databases in this server Database-LevelĭROP DATABASE databaseName - Delete the database (irrecoverable!)ĭROP DATABASE IF EXISTS databaseName - Delete if it existsĬREATE DATABASE databaseName - Create a new databaseĬREATE DATABASE IF NOT EXISTS databaseName - Create only if it does not exists Summary of MySQL Commands Used in this Tutorialįor detailed syntax, check MySQL manual "SQL Statement Syntax". In this tutorial, you have learned about database views and how to use the CREATE VIEW statement to create new views in SQLite.Read " How to Install MySQL and Get Started" on how to install, customize, and get started with MySQL. This query returns data from the v_albums view: SELECT * FROM v_albums Code language: SQL (Structured Query Language) ( sql ) In this example, we specified new columns for the view AlbumTitle for the albums.title column and Minutes for the expression SUM(milliseconds) / 60000 The following statement creates a view named v_albums that contains album title and the length of album in minutes: CREATE VIEW v_albums (Ĭode language: SQL (Structured Query Language) ( sql ) Try It 2) Creating a view with custom column names SELECT * FROM v_tracks Code language: SQL (Structured Query Language) ( sql ) To create a view based on this query, you use the following statement: CREATE VIEW v_tracksįrom now on, you can use the following simple query instead of the complex one above. INNER JOIN genres ON genres.GenreId = tracks.GenreId Code language: SQL (Structured Query Language) ( sql ) INNER JOIN media_types ON media_types.MediaTypeId = tracks.MediaTypeId INNER JOIN albums ON Albums.AlbumId = tracks.AlbumId The following query gets data from the tracks, albums, media_types and genres tables in the sample database using the inner join clause. 1) Creating a view to simplify a complex query Let’s take some examples of creating a new view using the CREATE VIEW statement. However, you can assign the names of the view columns that are different from the column name of the table By default, the columns of the view derive from the result set of the SELECT statement. Third, specify a SELECT statement for the view. The view is called a temporary view and SQLite automatically removes the temporary view whenever the database connection is closed. Second, use the the TEMP or TEMPORARY option if you want the view to be only visible in the current database connection. If the view already exists, it does nothing. The IF NOT EXISTS option only creates a new view if it doesn’t exist. To create a view, you use the CREATE VIEW statement as follows: CREATE VIEW view_nameĪS select- statement Code language: SQL (Structured Query Language) ( sql )įirst, specify a name for the view. It means you cannot use INSERT, DELETE, and UPDATE statements to update data in the base tables through the view.
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