Answer / nandini sett

Outer join displays result set containing all the rows from
one table and the matching rows from another table. There
are three types of Outer Join -- Left Outer Join (All rows
of the left table and matchng rows of the right), Right
Outer Join (All rows of the right table and matching rows
of the left table) and Full Outer Join (All rows of both
tables).
In self join, table is joined with itself. One row
correlates with other rows in the same table. Hence a table
name with two alias names is used.
Difference between outer join and self join is that outer
join uses atleast two or more tables where one column is
common while self join uses only one table and two fields
of the same table.
Cartesian Product or cross join is between two tables where
each row from one table with each row of the other table.
If table A has 5 rows and table B has 10 rows then after
cross join the total number of rows would be 50.

How do I kill a query in postgresql?

0 Answers  

---

what happens if null values are involved in expressions? : Sql dba

0 Answers  

---

What is a native sql query?

0 Answers  

---

What is the use of function in sql?

0 Answers  

---

Explain the significance of the & and && operators in pl sql.

0 Answers  

---

---

What is sql prepared statement?

0 Answers  

---

What are the indexing methods?

0 Answers  

---

What is a 'instead of trigger'?

3 Answers   Eenadu, TCS,

---

When a dml statement is executed, in which cursor attributes, the outcome of the statement is saved?

0 Answers  

---

Which nosql database is best?

0 Answers  

---

how to dump a table to a file with 'mysqldump'? : Sql dba

0 Answers  

---

IN A TABLE HAVE ONE COLUMN PRIMARY KEY..IT WILL NOT ALLOWS NULL VALUES AND DUPLICATE VALUES..INSTEAD OF PRIMARY KEY WHY CANT WE USE UNIQUE AND NOT NULL.THESE TWO ALSO DOESNT ACCEPT NULL VALUES IN NOT NULL AND UNIQUE DOESNT ACCEPT DUPLICATE VALUES? SO WHAT IS THE DIFEERENCE BETWEEN(UNIQUE,NOT NULL) AND PRIMARY KEY??????

8 Answers   rsystems,

---