true /false The system-defined database used as a template for all “to be created” databases is the tempdb database. The entire contents of this database, including database options, are copied to the new database. Thus, if you modify this database, all databases created afterward will inherit those changes. OUTER JOIN types return only non-matching tuples. When we create a primary key (PK) some Database Management Systems (DBMS) automaticallly create a Foreign Key constraint on the attributes of the PK. SQL Server DBMS is one of these DBMSs. If a relation has more than one candidate key, we can implement this by creating a Primary Key constraint for one of the candidate keys, and a UNIQUE constraint for each and every one of the alternate keys. Using the Query Editor Window, “select TOP 1000 Rows” retrieves the first 1000 tuples of a relation (assuming that the relation has 1000 or more tuples). If there is a referential integrity constraint between two relations, it means that one of the relations are referring to the other. When we try to delete the “referring relation”, the system will not let us do that as referring relation tuples refer (point) to the referenced relation tuples, and if we were able to delete the “referring tuples”, the database would be in an inconsistent state. If there is a DEFAULT constraint on an attribute a2 of a relation A, not speciifying the a2 attribute value in an INSERT INTO statement has the same effect as specifying its value as NULL. In other words, insert into A(a1, a2) values(3, NULL) ≡ insert into A(a1) values(3). While creating a CHECK constraint, if there are tuples violating the condition we specify as part of the CHECK constraint, “cascading” specification eliminates these inconsistencies. “cascading” specification causes all “violating tuples” to be deleted. The “*” character used in an SQL SELECT statement means “all the tuples”.
true /false
The system-defined
OUTER JOIN types return only non-matching tuples.
When we create a primary key (PK) some Database Management Systems (DBMS) automaticallly create a Foreign Key constraint on the attributes of the PK. SQL Server DBMS is one of these DBMSs.
If a relation has more than one candidate key, we can implement this by creating a Primary Key constraint for one of the candidate keys, and a UNIQUE constraint for each and every one of the alternate keys.
Using the Query Editor Window, “select TOP 1000 Rows” retrieves the first 1000 tuples of a relation (assuming that the relation has 1000 or more tuples).
If there is a referential integrity constraint between two relations, it means that one of the relations are referring to the other. When we try to delete the “referring relation”, the system will not let us do that as referring relation tuples refer (point) to the referenced relation tuples, and if we were able to delete the “referring tuples”, the database would be in an inconsistent state.
If there is a DEFAULT constraint on an attribute a2 of a relation A, not speciifying the a2 attribute value in an INSERT INTO statement has the same effect as specifying its value as NULL. In other words, insert into A(a1, a2) values(3, NULL) ≡ insert into A(a1) values(3).
While creating a CHECK constraint, if there are tuples violating the condition we specify as part of the CHECK constraint, “cascading” specification eliminates these inconsistencies. “cascading” specification causes all “violating tuples” to be deleted.
The “*” character used in an SQL SELECT statement means “all the tuples”.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps
