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The DROP COLUMN command is used to delete a column in an existing table. The following SQL deletes the "ContactName" column from the "Customers" table:
DROP COLUMN column_name; Code language: SQL (Structured Query Language) (sql) In this syntax: First, specify the name of the table that contains the column which you want to drop after the ALTER TABLE keywords. Second, specify the name of the column that you want to drop in the DROP COLUMN clause.
20 Ιαν 2021 · Create a new database: CREATE DATABASE database_name; Access a database: USE database_name; Delete a database (and drop all tables): DROP DATABASE database_name; List all databases on the MySQL server: SHOW DATABASES; List all MySQL users: SELECT user FROM mysql.user;
13 Απρ 2020 · To delete a single view use the DROP command: DROP VIEW [IF EXISTS] view_name; You can also delete multiple views at a time: DROP VIEW [IF EXISTS] view1, view2, ...;
DROP COLUMN name; To delete a table: DROP TABLE. animal; QUERYING DATA. To select data from a table, use the . SELECT. command. An example of a single-table query: SELECT species, AVG(age) AS average_age FROM animal WHERE id != 3 GROUP BY species HAVING AVG(age) > 3 ORDER BY AVG(age) DESC; An example of a multiple-table query: SELECT. city.name ...
ALTER TABLE table_name. DROP [COLUMN] column_name; Code language: SQL (Structured Query Language) (sql) Add an index with a specific name to a table on a column: ALTER TABLE table ADD INDEX [name](column, ...);
To create a database: CREATE DATABASE zoo; To list all the databases on the server: SHOW DATABASES; To use a specified database: USE zoo; To delete a specified database: DROP DATABASE zoo; To list all tables in the database: SHOW TABLES;
