Union page 1
The UNION keyword is used for integrating queries:
The UNION clause combines the results of two SELECT statements into a single result set. If the ALL parameter is given, all the duplicates of the rows returned are retained; otherwise the result set includes only unique rows. Note that any number of queries may be combined. Moreover, the union order can be changed with parentheses.
The following conditions should be observed:
Find the model numbers and prices of the PCs and laptops:
Find out the product type, the model number, and the price of the PCs and laptops: