УПР 121-150

Which clause is used to limit the number of rows returned?

• LIMIT

• TOP

• ROWNUM

• FETCH

How do you create an index in postgresql?

• CREATE INDEX index_name ON table_name(column_name);

• MAKE INDEX index_name ON table_name(column_name);

• BUILD INDEX index_name ON table_name(column_name);

• SET INDEX index_name ON table_name(column_name);

What is a foreign key?

• A key that links two tables together

• A key that always has a unique value

• A primary key of a table

• A temporary key for queries

Which SQL keyword is used to create a view?

• CREATE VIEW

• MAKE VIEW

• ADD VIEW

• SET VIEW

What command removes a view?

• DROP VIEW

• DELETE VIEW

• REMOVE VIEW

• CLEAR VIEW

What is the default isolation level in postgresql?

• Read Committed

• Serializable

• Repeatable Read

• Read Uncommitted

Which SQL keyword creates a copy of a table structure without data?

• CREATE TABLE new_table AS SELECT * FROM old_table WHERE FALSE;

• DUPLICATE TABLE old_table;

• COPY TABLE old_table;

• CLONE TABLE old_table;

What is the command to terminate a connection session in psql?

• \q

• \exit

• \logout

• \close

Which command is used to backup a postgresql database?

• pg_dump

• pg_backup

• pg_save

• pg_export

Which type of JOIN returns all records from both tables, matching where possible?

• FULL JOIN

• INNER JOIN

• LEFT JOIN

• RIGHT JOIN