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## 9.6. Union

Combining results from multiple queries is done through the `UNION` operator.

Combines the results of two or more queries into a single result set that includes all the rows that belong to all queries in the union.

The number and the names of the columns must be identical in all queries combined by using `UNION`.

To keep all the result rows, use `UNION` `ALL`. Using just `UNION` will combine and remove duplicates from the result set.

Figure 9.6. Graph

### 9.6.1. Combine two queries

Combining the results from two queries is done using `UNION ALL`.

Query.

    MATCH (n:Actor)
    RETURN n.name AS name
    UNION ALL MATCH (n:Movie)
    RETURN n.title AS name

The combined result is returned, including duplicates.

Result

name
4 rows
`"Anthony Hopkins"`
`"Helen Mirren"`
`"Hitchcock"`
`"Hitchcock"`

### 9.6.2. Combine two queries and remove duplicates

By not including `ALL` in the `UNION`, duplicates are removed from the combined result set

Query.

    MATCH (n:Actor)
    RETURN n.name AS name
    UNION
    MATCH (n:Movie)
    RETURN n.title AS name

The combined result is returned, without duplicates.

Result

name
3 rows
`"Anthony Hopkins"`
`"Helen Mirren"`
`"Hitchcock"`

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