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What does the following integrity constraint try to enforce? (integrity constraint is primary key in this case but I couldn't understand what I should really write).

Explain why the intended integrity constraint cannot be enforced?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

We are studying SQL at school.

Sabancı bilgisayara selamlar @yguney

What does the following integrity constraint try to enforce? (integrity constraint is primary key and check in this case but I couldn't understand what I should really write).

Explain why the intended integrity constraint cannot be enforced?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

We are studying SQL at school.

Sabancı bilgisayara selamlar @yguney

What does the following integrity constraint try to enforce? (integrity constraint is primary key in this case but I couldn't understand what I should really write).

Explain why the intended integrity constraint cannot be enforced?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

We are studying SQL at school.

What does the following integrity constraint try to enforce? (integrity constraint is primary key in this case but I couldn't understand what I should really write).

Explain why the intended integrity constraint cannot be enforced?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

We are studying SQL at school.

Sabancı bilgisayara selamlar @yguney

What does the following integrity constraint try to enforce  ? (integrity constraint is primary key in this case but i couldnt understand what should i really write  )

Explain why the intended integrity constraint cannot be enforced  ?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

What does the following integrity constraint try to enforce? (integrity constraint is primary key in this case but I couldn't understand what I should really write).

Explain why the intended integrity constraint cannot be enforced?

CREATE TABLE Sailors
( sid INTEGER,
  sname CHAR(10),
  rating INTEGER,
  age REAL,
  PRIMARY KEY (sid),
  CHECK
    ( (SELECT COUNT (S.sid) FROM Sailors S)
    + (SELECT COUNT (B.bid) FROM Boats B) < 100 )
) ;

We are studying SQL at school.