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 Related Questions These are attributes of one table that have matching values in a primary key in another table, allowing for relationships between tables. Latest Answer : Foreign Keys are keys used in a table as an attribute and are primary keys of some other table ... Referential integrity refers to the consistency that must be maintained between primary and foreign keys, ie every foreign key value must have a corresponding primary key value. Latest Answer : the relation of the primary key of a base table with foreign key of the reference table is known as referential integriety. ... Denormalizing DB2 tables reduces the need for processing intensive relational joins and reduces the number of foreign keys. Latest Answer : In datawarehouse environment, mostly all the tables are semi- normalized ( ie it is fully normalized) to reduce no of joins . so de-normalization is having lot of advantages in datawarehouse . ... Under what circumstances will DB2 allow an SQL statement to update more than one primary key value at a time? Never. Such processing could produce duplicate values violating entity integrity. Primary keys must be updated one at a time. A31. The self-referencing constraint limits in a single table the changes to a primary key that the related foreign key defines. The foreign key in a self referencing table must specify the DELETE CASCADE Tables related with a foreign key are called delete-connected because a deletion in the primary key table can affect the contents of the foreign key table. Never. New primary key values are not a problem. However, the values of foreign key inserts must have corresponding primary key values in their related tables. And updates of primary key values may require Primary key and foreign key columns; columns that have unique values; columns that have aggregates computed frequently and columns used to test the existence of a value. Target table T1 is getting deleted. Table T2 has the foreign key. We require that whenever a row from T1 is deleted, the corresponding row from T2 also be deleted. Which option can be used? a.ON DELETE
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