3.9

SELECT statement

A SQL command used to select data from a database.

INNER JOIN

A join operation that returns only the rows that have matching values in both tables.

CROSS JOIN

A join operation that returns the Cartesian product of two tables.

UNION operation

Combines all unique rows from two compatible tables into a single table.

INTERSECT operation

Returns only rows that appear in both tables.

MINUS operation

Removes rows from one table that appear in a second compatible table.

Aggregate function

A function that performs a calculation on a set of values and returns a single value.

GROUP BY clause

Used to arrange identical data into groups in SQL.

Query optimizer

A component that converts an SQL query into a sequence of low-level database actions.

Query execution plan

A sequence of steps used to access and manipulate data based on a SQL query.

Data type compatibility

The requirement that two tables must have the same number of columns with compatible data types to perform set operations.

Theta join

A type of join that uses a specific condition to match rows from two tables.