Fichas
Sin título
Fichas del conjunto (8)
- 1The ROLLUP operation is only allowed withinthe GROUP BY clause
- 2What is TRUE regarding the EXISTS operator used in the correlated subqueries?- The outer query stops evaluating the result set of inner query when the first value is found
- It is used to test whether the values retrieved by the outer query exist in the result set of the inner query - 3A non-corelated subquery can be defined asa set of one or more sequential queries in which generally the result of the inner query is used as the search value in the outer query
- 4Which statements are correct regarding indexes?- when a table is dropped, the corresponding indexes are automatically dropped
- for each DML operation performed, the corresponding indexes are automatically updated
- a non-deferrable PRIMARY KEY or UNIQUE KEY constraint in a table automatically creates a unique index - 5What best describes the GROUPING function?It is used to identify if the NULL value in an expression is a stored NULL value or created by ROLLUP or CUBE.
- 6Which two statements are true regarding operators used with subqueries?- the
- 7Which statement is true regarding the ROLLUP operator specified in the GROUP BY clause of a SQL statement?It produces higher-level subtotals, moving from right to left through the list of grouping columns specified in the GROUP BY clause
- 8Which two statements are true regarding multiple-row subqueries?- They can contain group functions
- They should not be used with the NOT IN operator in the main query if NULL is likely to be a part of the result of the subquery
Información
- Descripción
- Fichas sobre Sin título, creado por anillvap el 28/01/2014.
- Creado por
- anillvap · ene 2014
- Actualizado
- 19 feb 2016
- Visitas
- 14
- Valoración