Which types of subqueries does Snowflake support? (Select TWO).
Correct Answer: B,E
Snowflake supports a variety of subquery types, including both correlated and uncorrelated subqueries. The correct answers are B and E, which highlight Snowflake's flexibility in handling subqueries within SQL queries.
* Uncorrelated Scalar Subqueries:These are subqueries that can execute independently of the outer query. They return a single value and can be used anywhere a value expression is allowed, offering great flexibility in SQL queries.
* EXISTS, ANY/ALL, and IN Subqueries:These subqueries are used inWHEREclauses to filter the results of the main query based on the presence or absence of matching rows in a subquery. Snowflake supports both correlated and uncorrelated versions of these subqueries, providing powerful tools for complex data analysis scenarios.
* Examples and Usage:
* Uncorrelated Scalar Subquery:
SELECT*FROMemployeesWHEREsalary > (SELECTAVG(salary)FROMemployees);
* Correlated EXISTS Subquery:
SELECT*FROMorders oWHEREEXISTS(SELECT1FROMcustomer cWHEREc.id =
o.customer_idANDc.region ='North America');
Reference:For comprehensive details on the types of subqueries supported by Snowflake and examples of their usage, consult the Snowflake documentation on subqueries:
https://docs.snowflake.com/en/sql-reference/constructs/subqueries.html