Which two statements are true about foreign key constraints、 (Choose two.)

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• 1Which statement about triggers is true、

  A.A trigger is designed to return specific types of values and contains executable code.

  B.A trigger is designed to return specific types of values but contains no executable code.

  C.A trigger performs actions to capture details about an activity like a join operation against multiple tables.

  D.A trigger performs actions in response to an event like an INSERT, UPDATE or DELETE operation on a tabl

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• 2When a user-defined function (UDF) is created and no schema is specified, what schema is used to store the UDF、

  A.The SYSIBM schema.

  B.The SYSFUN schema.

  C.A schema with the name of the UDF.

  D.A schema with the userid of the UDF definer.

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• 3When an application using a temporary table terminates or disconnects from the databaseunexpectedly, what happens to the temporary table and any data stored in it、

  A.The data in the table is deleted and the table persists.

  B.The data in the table is deleted and the table is implicitly dropped.

  C.The temporary table is converted to a base table and the data is delete

  D.D. The temporary table is converted to a base table and the data is persistent.

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• 4A table named STATES was created as follows:  CREATE TABLE states  (state_cd     CHAR(2) NOT NULL,   state_desc   CHAR(20)); CREATE UNIQUE INDEX indx1 ON states (state_cd); What will happen、

  A.An error will be returned and the operation will fail.

  B.A warning will be returned and the unique index INDX1 will become the index for the primary key.

  C.The primary key will be successfully added and the unique index INDX1 will be dropped and recreatedas the primary key index.

  D.The primary key will be successfully added, the unique index INDX1 will be dropped, and a new indexwill be created for the primary key.

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• 5Which statement regarding triggers is true、

  A.Only one INSERT, UPDATE, or DELETE trigger can be defined per table.

  B.Triggers cannot be modified, they must be dropped and recreated with new definitions.

  C.Adding a trigger to a table that already has rows in it will cause triggered actions to be fire

  D.D. Triggers can only be fired one time per statement irrespective of the number of rows affected.

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• 6What is the primary purpose of a view、

  A.To enable uniqueness.

  B.To ensure data clustering.

  C.To combine data from multiple tables.

  D.To optimize queries ran against multiple tables.

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• 7By default, a column defined as a TIMESTAMP includes which attributes、

  A.No fractional digits or time zone.

  B.6 fractional digits and no time zone.

  C.12 fractional digits plus a time zone.

  D.12 fractional digits and no time zon

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• 8Which is NOT a valid reason for creating an index、

  A.To allow queries to run more efficiently.

  B.To enforce constraints such as uniqueness on index keys.

  C.To order the columns of a table in ascending or descending sequence according to values in a row.

  D.To order the rows of a table in ascending or descending sequence according to the values in a column.

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• 9Which type of constraint can be used to ensure that an INTEGER column in a table will never be assigned more than one record that contains a NULL value、

  A.Unique constraint

  B.Primary key constraint

  C.Informational constraint

  D.Column default constraint

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• 10Which statement is true regarding constraints、

  A.A table can only have one unique key constraint.

  B.A table can have multiple primary key constraints.

  C.Informational constraints tell DB2 what rules the data conforms to, but the rules are not enforce

  D.D. Foreign key constraints are enforced on the values within the rows of a table, or between the rows of two tables, by a unique index on a foreignkey.

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