what is the use of system.effective.date variable in oracle?

0 Answers  

---

WHAT IS THE DIFFERENCE BETWEEN PRIMARY KEY(PK) CONSTRAINT AND UNIQUE KEY(UK) + NOT NULL(NN) CONSTRAINT ASSIGN TO A COLUMN ? INSTEAD OF ASSIGNING PK ,WE CAN ASSIGN UK + NN TO A COLUMN. WHAT ARE THE MARRITS AND DEMARITS BETWEEN THE ABOVE TWO?THE ABOVE TWO ARE SAME,THEY DON'T ALLOW DUPLICATE AS WELL AS NULL VALUES.

3 Answers  

---

What are the four Oracle system processes that must always be up and running for the database to be useable?

0 Answers  

---

If a table column has is UNIQUE and has NOT NULL, is it equivalent to a PRIMARY KEY column?

7 Answers   IBM,

---

It's Urgent? How to IMPORT .xls & .txt file into ORACLE?

5 Answers  

---

---

How to fetch the row which has the max value for a column?

0 Answers  

---

What are the different types of record groups in oracle? Explain each of them

0 Answers  

---

How to increment dates by 1 in oracle?

0 Answers  

---

waht is referencial integrity?

2 Answers   Semantic Space,

---

What is the difference between column level constraints and table level constraints?

14 Answers   IBM, TCS,

---

write a query that displays every Friday in a year with date?

5 Answers   Flipkart, HCL, TCS,

---

query to find the maximum no persons with same age(age colomn) from emp table

1 Answers  

---