CREATE TABLE keshi(           kname VARCHAR(5) PRIMARY KEY,           address VARCHAR(5),           tele INT,           dname VARCHAR(10))DESC keshi;CREATE TABLE bingfang(           bid INT PRIMARY KEY,           chuangwei INT,           kname VARCHAR(5),           CONSTRAINT bingfang_keshi_fk           FOREIGN KEY (kname) REFERENCES           keshi(kname)           )DESC bingfang;CREATE TABLE yisheng(           dname VARCHAR(5) PRIMARY KEY,           zhicheng VARCHAR(10),           kname VARCHAR(5),           age INT,           gongzuozhenghao INT,           CONSTRAINT yisheng_keshi_fk           FOREIGN KEY (kname) REFERENCES           keshi(kname))DESC yisheng;CREATE TABLE bingren(          bingli INT,          rname VARCHAR(5),          sex VARCHAR(2),          zhenduan VARCHAR(20),          dname VARCHAR(5),          bid INT,          CONSTRAINT bingren_yisheng_fk          FOREIGN KEY (dname) REFERENCES          yisheng(dname))DESC bingren;