Single vs Multiple primary keys

[Bartis, Robert M (Bob)]

I have a table, see below, that contains a single primary key (SubTestCaseKey ) 
and a number of foreign keys   

*       plantriggers_ID_FK ,
*       testcase_root_ID_FK 
*       testcasesuffix_name_FK 

What I want to ensure is that there are no duplicate records when considering 
the three foreign keys above. Would it be appropriate to remove the single 
primary and replace with three multiple primary keys? Is there a performance 
impact when doing this. this seems overly complex and wonder if I should be 
breaking the table up to simplify? Any suggestions would be appreciated.
 
Bob
 
CREATE TABLE testplans (
  SubTestCaseKey INTEGER NOT NULL AUTO_INCREMENT,
  plantriggers_ID_FK INTEGER UNSIGNED NOT NULL,
  testcase_root_ID_FK INTEGER NOT NULL,
  testcasesuffix_name_FK VARCHAR(20) NULL,
  FSAGA ENUM('FSA1','FSA2','GA') NULL DEFAULT 'GA',
  Priority ENUM('P1','P2','P3','Do Not Run') NULL DEFAULT 'Do Not Run',
  DateMod TIMESTAMP NULL,
  tester_list_Name_FK VARCHAR(50) NULL,
  PRIMARY KEY(SubTestCaseKey),
  INDEX testplans_FKIndex1(tester_list_Name_FK),
  INDEX testplans_FKIndex2(testcasesuffix_name_FK),
  INDEX testplans_FKIndex3(testcase_root_ID_FK),
  INDEX testplans_FKIndex4(plantriggers_ID_FK),
  FOREIGN KEY(tester_list_Name_FK)
    REFERENCES tester_list(Name)
      ON DELETE RESTRICT
      ON UPDATE CASCADE,
  FOREIGN KEY(testcasesuffix_name_FK)
    REFERENCES testcasesuffix(name)
      ON DELETE RESTRICT
      ON UPDATE CASCADE,
  FOREIGN KEY(testcase_root_ID_FK)
    REFERENCES testcase_root(ID)
      ON DELETE RESTRICT
      ON UPDATE CASCADE,
  FOREIGN KEY(plantriggers_ID_FK)
    REFERENCES plantriggers(ID)
      ON DELETE RESTRICT
      ON UPDATE CASCADE
)
TYPE=InnoDB;
 

Robert M. Bartis 
Lucent Technologies, Inc 
Tel: +1 732 949 4565 
Mail: <[EMAIL PROTECTED]> 
Pgr: <[EMAIL PROTECTED]>