![]() Rows in the left operand that do not exist in the right operand. The set difference from both subqueries without duplicates. Duplicate entries in the result are eliminated. All of the rows that appear inīoth operands are accounted for in the result. The intersection from both subqueries without duplicates. All of the rows from both operandsĪre taken into account. The Aliases are more useful when multiple columns or multiple tables are used in a single. The set union from both subqueries without duplicates. The purpose of Aliases is to make table or column names more readable. All of the rows from both operands are taken into account. Each column gets assigned a single name. (It's not possible to specify two different aliases for one column in the resultset. The column names and aliases in subsquent queries are ignored. ![]() These calculate the set union, the set union without duplicates, the intersection without duplicates, and the set difference without duplicates from two subqueries. With a UNION and UNION ALL set operators, the column names for the resultset are specified in the first SELECT. To combine the results of various queries with one another, the table operators UNION ALL, UNION, INTERSECT, and MINUS (=EXCEPT) exist. SQL aliases are custom names that you can give to the columns and tables you include in your queries. The best way to master aliases in SQL is practice. We’ll be taking a closer look at using SQL aliases with JOIN and why you might need to do so. Aliases are very useful, as they can greatly improve the readability and maintainability of your query. Table Operators - UNION, INTERSECT, MINUS Purpose SQL aliases are custom names that you can give to the columns and tables you include in your queries. ![]()
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