What are the keywords that represent union in sql

In SQL, the keyword for union is UNION, which is used to combine the results of multiple SELECT statements into a single result set that contains all unique rows.

Keywords representing union in SQL

In SQL, the keywords representing union are:

• UNION

Using UNION

UNION keyword is used for Combines the results of two or more SELECT statements into a single result set. The result set contains all unique rows from both input tables.

Syntax:

<code class="sql">SELECT 列名1, 列名2, ...
FROM 表名1
UNION
SELECT 列名1, 列名2, ...
FROM 表名2;</code>

For example:

<code class="sql">SELECT name, city
FROM table1
UNION
SELECT name, city
FROM table2;</code>

The above query will return table1 and table2 The name and city columns for all unique rows in the table.

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