SQL –UNION

DIFFERENCE BETWEEN UNION AND UNION ALL | EXAMPLE | UNION QUERY | UNION ALL QUERY | PRACTICE YOURSELF

SQL UNION is used to combine the result sets of two or more SELECT Statements, provided they satisfy the below conditions:

• Each SELECT statement within UNION should have the equal number of columns

• The columns must also have similar data types

• The columns in each SELECT statement must also be in the same order

SYNTAX

Where,

• UNION : KEYWORD used to combine the result set of both the tables

Difference between UNION AND UNION ALL

• UNION removes duplicate rows.

• UNION ALL does not remove duplicate rows.

SYNTAX

EXAMPLE

Let’s consider a Demo Database with Table Individual and Address

Figure 37.1. Individual TABLE

UNION QUERY

​

UNION ALL QUERY

PRACTICE YOURSELF

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