What happens when subquery returns more than one row?

What happens when subquery returns more than one row?

select * from table where id= (multiple row query); Where multiple row query returns multiple rows. So if the values from those rows are 1,2,3 then I want to set id to be 1 or 2 or 3.

How do you fix more than one row returned by a subquery used as an expression?

6 Answers

1. Technically, to repair your statement, you can add LIMIT 1 to the subquery to ensure that at most 1 row is returned.
2. Practically, you want to match rows somehow instead of picking an arbitrary row from the remote table store to update every row of your local table customer .

How do I stop single row subquery returns more than one row?

Try to add and rownum=1 to your subquery conditions if you DO NOT care about the value from the list or DO sure that they are the same. A single row subquery returns only one row. It can be used with the equal comparison operators (=,<,>,<>, etc).

What is subquery in PSQL?

A subquery is a SQL query nested inside a larger query. In PostgreSQL subquery can be nested inside a SELECT, INSERT, UPDATE, DELETE, SET, or DO statement or inside another subquery. A subquery is usually added within the WHERE Clause of another SQL SELECT statement.

How do I create a sub query in PostgreSQL?

A subquery is a query nested inside another query such as SELECT, INSERT, DELETE and UPDATE ….PostgreSQL executes the query that contains a subquery in the following sequence:

1. First, executes the subquery.
2. Second, gets the result and passes it to the outer query.
3. Third, executes the outer query.

Can a single row subquery returns more than one column?

Although this query type is formally called “single-row,” the name implies that the query returns multiple columns-but only one row of results. However, a single-row subquery can return only one row of results consisting of only one column to the outer query.