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Showing 1661–1680 of 2015 results

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SQL and relational databases · Multiple Choice
Difficulty: Medium
Which constraint prevents duplicate permitted key values under the database's null-handling rules?
ConstraintsData integrity
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SQL and relational databases · Multiple Choice
Difficulty: Medium

Which constraint rejects rows when a specified Boolean condition evaluates to false?

ConstraintsData integrity

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which column constraint forbids storing a null value in that column?

ConstraintsData integrity

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which common SQL statement starts an explicit transaction block?

Transaction controlAtomic changes

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL statement successfully completes a transaction and makes its committed effects durable under the database's guarantees?

Transaction controlAtomic changes

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL statement abandons the uncommitted changes in the current transaction?

Transaction controlAtomic changes

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL statement marks an intermediate transaction position that can be rolled back to?

Transaction controlAtomic changes

SQL and relational databases · Multiple Choice

Difficulty: Medium

What mode treats each standalone statement as its own transaction unless a transaction is explicitly opened?

Transaction controlAtomic changes

SQL and relational databases · Multiple Choice

Difficulty: Easy

Which SQL predicate correctly tests whether an expression has a null value?

Predicates and conditional valuesQuery expressions

SQL and relational databases · Multiple Choice

Difficulty: Easy

Which SQL predicate tests membership in a supplied list or subquery result?

Predicates and conditional valuesQuery expressions

SQL and relational databases · Multiple Choice

Difficulty: Easy

Which SQL predicate tests whether a subquery returns at least one row?

Predicates and conditional valuesQuery expressions

SQL and relational databases · Multiple Choice

Difficulty: Easy

Which SQL predicate tests an inclusive lower and upper bound?

Predicates and conditional valuesQuery expressions

SQL and relational databases · Multiple Choice

Difficulty: Easy

Which SQL expression selects a result value according to conditions or matching alternatives?

Predicates and conditional valuesQuery expressions

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL set operation combines compatible query results and removes duplicate rows?

Set operationsCombining results

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL set operation combines compatible query results while retaining duplicates?

Set operationsCombining results

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL set operation returns rows occurring in both compatible input results?

Set operationsCombining results

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL set operation returns rows from the left result that do not occur in the right result?

Set operationsCombining results

SQL and relational databases · Multiple Choice

Difficulty: Medium

Which SQL construct repeatedly references its own intermediate result to traverse a hierarchy or similar relation?

Set operationsCombining results

SQL and relational databases · Multiple Choice

Difficulty: Medium

What named query expression introduced with WITH can be referenced by a larger SQL statement?

Query toolsComposition and planning

SQL and relational databases · Multiple Choice

Difficulty: Medium

What is a query nested inside another SQL statement called?

Query toolsComposition and planning

Showing 1661–1680 of 2015 results

1…83 84 85…101