In SQL, the OR operator allows you to use alternative conditions when filtering your queries.
The OR operator combines two conditions, and returns TRUE when either of the conditions is TRUE.
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SQL EXISTS Operator for Beginners
In SQL, the EXISTS operator specifies a subquery to test for the existence of rows. It returns TRUE when the subquery returns one or more rows.
A subquery is a query that is nested inside another query (or even another subquery)
This article contains some basic examples of the EXISTS operator.
SQL CREATE TABLE … AS SELECT Statement
The SQL CREATE TABLE ... AS SELECT statement enables you to insert the results of a query into a new table.
SQL INSERT INTO… SELECT Examples
The SQL INSERT statement is most commonly used to insert individual rows into a table.
But you can also insert the results of a query into a table. This means that you can insert multiple rows at once (as long as they’re returned by the query).
SQL Self Join
This article provides an overview of the self join in SQL, as well as a basic example.
SQL Natural Join
This article provides an overview of the natural join in SQL, as well as some basic examples.
SQL Full Join
This article provides an overview of the FULL JOIN in SQL, as well as some basic examples.