DBMS Types Data Independence Three schema architecture DBMS users Dr.E.F.Codd’s rules for RDBMS (0-12) ER Model SQL DDL – CREATE, ALTER, DROP, TRUNCATE, RENAME DML – INSERT, UPDATE, DELETE DCL – GRANT, REVOKE, CREATE USER, DROP USER TCL – COMMIT, ROLLBACK, SAVEPOINT DATATYPES, OPERATORS(ARITHMETIC,RELATIONAL) CONSTRAINTS (PRIMARY KEY, FOREIGN KEY, NOT NULL, UNIQUE, CHECK) WHERE CLAUSE ORDER BY ASC | DESC DISTINCT GROUP BY - HAVING FUNCTIONS 1. SINGLE ROW FUNCTIONS(UPPER,LOWER,SUBSTR,INITCAP,LENGTH,TRIM,LTRIM,RTRIM) 2. AGGREGATE FUNCTIONS(MIN,MAX,SUM,AVG,COUNT) 3. NUMBER FUNCTIONS(ROUND,CEIL,FLOOR,ABS,MOD,SQRT,POWER) 4. DATE FUNCTIONS(TO_DATE,ADD_MONTHS,TO_CHAR,NEXTDAY,MONTHS_BETWEEN, SYSDATE) 5. NULL FUNCTIONS(NVL,NVL2,COALESCE) OPERATORS IN NOT IN BETWEEN AND IS NULL LIKE, NOT LIKE PATTERN MATCHING IS ...
Here is the solution:
ReplyDelete= != == ;
equals to IS NOT EQUAL TO double equals
equals is used to assign a value to a variable
Ex. int a = 100;
int b = 200;
double equals to is used to check if two variables contain equal value.
ex. a = 10; b=20;
a==b returns false because a and b values are not equal
; is a statement terminator
very simple.....