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				CREATE TABLE STUDENTTBL
				(
				   STUDENT_ID VARCHAR(8) NOT NULL,
				   NAME VARCHAR(30),
				   PRIMARY KEY(STUDENT_ID)
				);
				
				CREATE TABLE COURSETBL
				(
				   COURSE_ID VARCHAR(8) NOT NULL,
				   NAME VARCHAR(30),
				   PRIMARY KEY(COURSE_ID)    
				);
				
				CREATE TABLE ENROLLTBL
				(
				   STUDENT_ID VARCHAR(8) NOT NULL,
				   COURSE_ID VARCHAR(8) NOT NULL,
				   PRIMARY KEY(STUDENT_ID,COURSE_ID)   
				);