HAPPY INSURANCE

Observe the HAPPY INSURANCE DATABASE:
CLIENT AGENT

Multiple Choice

HAPPY INSURANCE

Observe the HAPPY INSURANCE DATABASE:
CLIENT
$$\begin{array} { l l c l } \text { ClientID } & \text { ClientName } & \text { CientAgent } & \text { ClientSpouseName } \\\text { C111 } & \text { Tom } & \text { A1 } & \text { Jenny } \\\text { C222 } & \text { Kain } & A 1 & \text { Bill } \\\text { C333 } & \text { Cole } & A 2 & \text { Amy } \\\text { C444 } & \text { Dorothy } & A 2 & \\\text { C555 } & \text { Anay } & A 3 & \text { Amy } \\\text { C666 } & \text { Tina } & A 3 & \text { Matt } \\\text { C777 } & \text { Christina } & A 4 & \text { Mike }\end{array}$$ AGENT
$$\begin{array} { l l l l l c } \text { AgentID } & \text { AgentName } & \text { AgentArea } & \text { AgentRating } & \text { AgentYearofHire } & \text { SupervisedBy } \\\text { A1 } & \text { Kate } & 1 & 101 & 1990 & \\\text { A2 } & \text { Amy } & 2 & 92 & 2009 & \text { Al } \\\text { A3 } & \text { Luke } & 3 & 100 & 1992 & \\\text { A4 } & \text { James } & 3 & 90 & 2010 & \text { A3 }\end{array}$$ AREA
$$\begin{array} { l l l } \text { ArealD } & \text { AreaName } & \text { AreaHQ } \\1 & \text { East } & \text { Boston } \\2 & \text { West } & \text { San Francisco } \\3 & \text { Central } & \text { Chicago }\end{array}$$

This database will be used for the following questions citing tables from the HAPPY INSURANCE database.
-If a DBMS enforces an UPDATE SET-TO-NULL option on the referential integrity constraint between CLIENT and AGENT in the HAPPY INSURANCE database,what will be the outcome after a User tries to change the AgentID value in the last record to A5?

A) Value A4 appears once in column AgentID in AGENT,and value A4 appears once in column ClientAgent in table CLIENT
B) Value A5 appears once in column AgentID in AGENT,and value A5 appears once in column ClientAgent in table CLIENT
C) Value A5 appears once in column AgentID in AGENT,and value A5 does not appear in column ClientAgent in table CLIENT
D) Value A5 does not appear in column AgentID in AGENT,and value A5 appears once in column ClientAgent in table CLIENT