Sublanguages
This sublanguage is used to define the structure of a database.
DDL (Data Definition Language)
This type of SQL element is a specific value like a character string or a number.
Literal
This type of statement begins with the keyword SELECT and ends with a semicolon.
Query
Which statement shows all databases in a MySQL database system?
SHOW DATABASES;
This type of key uniquely identifies each row in a database table and cannot contain NULL values.
Primary Key
This sublanguage is used to retrieve data from the database.
DQL (Data Query Language)
Words such as SELECT, INSERT, and UPDATE fall under this category of language elements.
Keywords
Each SQL statement is made up of one or more of these.
Clauses
Which statement shows all tables in the current default database?
SHOW TABLES
This type of key in one table references the primary key of another table.
Foreign Key
This sublanguage is responsible for inserting, updating, and deleting data.
DML (Data Manipulation Language)
Name given to a database object, such as a column, table, or database.
Identifier
This clause is used to specify which columns to retrieve in a query.
SELECT
What SQL statement is used to delete an existing database named 'library'?
DROP DATABASE library;
This constraint ensures that a column cannot contain NULL values.
NOT NULL
This sublanguage is used to manage transactions, including committing and rolling back changes.
DTL (Data Transaction Language)
This element is a combination of literals, identifiers, and operations that evaluate to a single value.
Expression
This clause filters records that meet a specified condition.
WHERE
What SQL statement is used to create a new database named 'school'?
CREATE DATABASE school;
When multiple columns are needed to uniquely identify a row, this type of primary key is used.
Composite Primary Key
This sublanguage controls user access to the database.
DCL (Data Control Language)
This element is ignored by the SQL processor and used for explanation or documentation.
Comment
This clause is used to identify the table being queried.
FROM
Which SQL statement is used to change the name of a column or remove a column from an existing table?
ALTER TABLE
One way to maintain referential integrity is to delete all dependent records when a primary key is deleted. This action is called ____.
CASCADE delete.