Which operator is used to combine the results of two queries into a single result?
Summary: in this tutorial, you will learn how to use MySQL Show
MySQL UNION operatorMySQL
To combine result set of two or
more queries using the
By default, the Let’s see the following sample tables:
The following statement combines result sets returned from
The final result set contains the distinct values from separate result sets returned by the queries:
Because the rows with value 2
and 3 are duplicates, the The following Venn diagram illustrates the union of two result sets that come from If you use the
As you can see, the duplicates appear in the combined result set because of the UNION vs. JOINA MySQL UNION and column alias examplesWe’ll use the Suppose that
you want to combine the first name and last name of employees and customers into a single result set, you can use the
As you can see from the output, the MySQL
If you want to use other column headings, you need to use column aliases explicitly in the first
This example uses the column heading of the first query for the output. It uses the MySQL UNION and ORDER BYIf you want to sort the result set of a union, you use an
Notice that if you place the To differentiate between employees and customers, you can add a column as shown in the following query:
MySQL also provides you with an alternative option to sort a result set based on column position using
However, it is not a good practice to sort the result set by column position. In this tutorial, you have learned how to use MySQL
Was this tutorial helpful? Which operators combine the results of two component queries into a single result?Set operators combine the results of two component queries into a single result. Queries containing set operators are called compound queries. Table 4-4 lists SQL set operators.
What would be used to combine the results from two queries?The SQL UNION operator is used to combine the results of two or more queries into a distinct single result set.
Which operator is used to combine two or more queries?The SQL UNION Operator
The UNION operator is used to combine the result-set of two or more SELECT statements.
Which operator combines two queries into one result set and includes only data that is common to the combined queries?The UNION set operator combines the qualifying rows from two queries into a single result set that consists of the distinct rows that either or both of the queries returned. (If you also include the ALL keyword, the UNION ALL result set can include duplicate rows.)
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