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If you execute this query
SELECT 'test-a1' AS name1, 'test-a2' AS name2
the result will be a one row-selection with two columns having these values:
test-a1, test-a2
How can I modify the above query to have a selection with several rows, e.g.
test-a1, test-a2
test-b1, test-b2
test-c1, test-c2
I know how to do this with UNION but I feel that there exists a more simple way to do it.
PS. Sorry for such a basic question, it is very hard to google it.
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Syntax - SELECT column1,column2, …, columnN FROM table_name; column1,column2 – Specifies the name of the columns used to fetch. table_name - Specifies the name of the table.
To select multiple columns from a table, simply separate the column names with commas! For example, this query selects two columns, name and birthdate , from the people table: SELECT name, birthdate FROM people; Sometimes, you may want to select all columns from a table.
To select rows using selection symbols for character or graphic data, use the LIKE keyword in a WHERE clause, and the underscore and percent sign as selection symbols. You can create multiple row conditions, and use the AND, OR, or IN keywords to connect the conditions.
Values keyword can be used as below.
select * from (values ('test-a1', 'test-a2'), ('test-b1', 'test-b2'), ('test-c1', 'test-c2')) x(col1, col2) The following will work for SQL:
SELECT 'test-a1' AS name1, 'test-a2' AS name2
UNION ALL
SELECT 'test-b1', 'test-b2'
UNION ALL
SELECT 'test-c1', 'test-c2'
UNION ALL is the best bet. It's faster than UNION and you will have mutually exclusive rows.
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