MySQL 5.5

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select version();


version()


5.5.62


CREATE TABLE supplier (
  supplierNum CHAR(2)   NOT NULL,
  name CHAR(10) NOT NULL,
  status TINYINT(4) NOT NULL,
  city VARCHAR(10)  NOT NULL,
   PRIMARY KEY (supplierNum)
);
CREATE TABLE supplies (
  supplierNum CHAR(2) NOT NULL,
  partNum CHAR(2) NOT NULL,
  quantity SMALLINT(6) NOT NULL,
  PRIMARY KEY (supplierNum, partNum),
  FOREIGN KEY (supplierNum) REFERENCES supplier (supplierNum)
);
insert into supplier values(1, 'ABC', 1, 'Delhi');
insert into supplier values(2, 'XYZ', 2, 'Tokyo');
insert into supplies values(1, 'A1', 5);
insert into supplies values(2, 'B1', 9);
insert into supplies values(2, 'C2', 6);
insert into supplies values(2, 'Q1', 2);
select* from supplies;
Select * from supplier;


supplierNum
partNum
quantity


1
A1
5

2
B1
9

2
C2
6

2
Q1
2




supplierNum
name
status
city


1
ABC
1
Delhi

2
XYZ
2
Tokyo


SELECT sp.name
FROM supplier AS sp
INNER JOIN 
  (
  SELECT distinct supplierNum 
  FROM supplies
  GROUP BY supplierNum
  HAVING COUNT(supplierNum) > 1
  ) as cnt
 ON sp.supplierNum = cnt.supplierNum;


name


XYZ