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Store Procedure in Oracle

admin — Sun, 15 May 2011 07:26:05 +0000

Store Procedure in Oracle

By: Pankaj Yadav

Store procedures are the sub programs used to perform some actions. Mainly a procedure has two parts Specification and body .The Procedure is created with Create and ends with end procedure. The body of the store procedure stats after the IS or AS.

The Uses of procedures

1. They help us to make program in small manageable parts.

2. They make the code reusable

3. They help us to meet our need

syntax:

Create or replace Procedure [procedure name](Parameter1 [mode] ,..)
As
{Local variable declaration}
Begin
{Procedure statements}
end {procedure name}

Note: Replace is used if the procedure exists previously, replace it with the new one

Modes of Parameters :

There are 3 modes of parameters in store procedure. They are as follows

IN mode parameter is used to pass the value to the called procedure and in program it acts like constant

OUT mode parameter allows us to return the values from store procedure. In a store procedure the OUT parameter s are act like uninitialized parameters. So we cannot assign value to these

INOUT mode parameters allow both to return the value from subprogram

We Can execute a store procedure with the keyword ‘exec’

syntax for executing store procedure :

exec  {Procedure name}(Parameters)

Example:

create procedure minno(firstno in Number, secondno in Number)
returning integer;
 if (firstno < secondno) then
  return firstno;
 else
  return secondno;
 end if;
end minno

if we execute this procedure

exec  minno(20,10)

Output will be

SQL Joins in Oracle

admin — Sun, 01 May 2011 06:49:05 +0000

By: Pankaj Yadav

Oracle Join is basically used when we want to see the data from two or more tables at a same time. The data of the table got merged with the other table having a same column.

Joining Tables using Oracle Syntax

SELECT table1.column, table2.column
FROM table1, table2
WHERE table1.column1 = table2.column2;

Use a join to query data from more than one table.

Write the join condition in the WHERE clause.
Prefix the column name with the table name when the same column name appears in more than one table

We can declare fields as follows:

table1.column     --denotes the table and column from which data is retrieved
table1.column1 = table2.column2  --condition that joins (or relates) the tables together

We have various types of joins which are given below:

1. Equi join
2. Non-Equi join
3. Outer join
4. Self join
5. Cross join
6. Natural join

1. Equi join

It is the simplest join or inner. This type of join involves primary and foreign key complements.

2. Non Equi join

It is a join condition containing something other than equality operator.

3. Outer Join

We use outer join to also see rows that do not meet join condition. The outer join operator is plus sign (+).

SELECT table1.column, table2.column
FROM table1, table2
WHERE table1.column (+) = table2.column;
SELECT table1.column, table2.column
FROM table1, table2
WHERE table1.column = table2 .column(+);

The missing rows can be returned if an outer join operator is used in the join condition. The operator is a plus sign enclosed in parentheses (+), and it is placed on the “side” of the join that is deficient in Information. This operator has the effect of creating one or more null rows, to which one or more rows from the no deficient table can be joined.

table1.column = is the condition that joins (or relates) the tables together.
table2.column (+) is the outer join symbol, which can be placed on either side of the
WHERE clause condition, but not on both sides. (Place the outer
Join symbol following the name of the column in the table without

4. Self Join

This join can be performed when we have to join the single table to itself.

5. Cross join

This join returns the cross product of the records.

6. Natural join

The NATURAL JOIN clause is based on all columns in the two tables that have the same name. It selects rows from the two tables that have equal values in all matched columns. If the columns having the same names have different data types, an error is returned.

SQL – ifnull() Example, ifnull() function

admin — Sat, 28 Nov 2009 09:27:39 +0000

SQL ifnull() function is used find null value in rows and returns value on our condition if null value found in column from database table name, otherwise if column value is not null it will return column value.

SQL ifnull() query example explains how to use ifnull() query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       7 | Gagan Deep  | B.Tech     |       NULL |
|       8 | Mohit Garg  | M.Tech     |       NULL |
+---------+-------------+------------+------------+

ifnull() examples

SELECT  Name, Year_Start, IFNULL(Year_Start,0) FROM class_name c;

Output

+-------------+------------+----------------------+
| Name        | Year_Start | IFNULL(Year_Start,0) |
+-------------+------------+----------------------+
| Amit Mishra |       2005 |                 2005 |
| Robot       |       2005 |                 2005 |
| Rohan       |       2005 |                 2005 |
| Vivek       |       2009 |                 2009 |
| Chander     |       2009 |                 2009 |
| Deepak      |       2009 |                 2009 |
| Gagan Deep  |       NULL |                    0 |
| Mohit Garg  |       NULL |                    0 |
+-------------+------------+----------------------+

SELECT  Name, Year_Start, IFNULL(Year_Start,2000) FROM class_name c;

Output

+-------------+------------+-------------------------+
| Name        | Year_Start | IFNULL(Year_Start,2000) |
+-------------+------------+-------------------------+
| Amit Mishra |       2005 |                    2005 |
| Robot       |       2005 |                    2005 |
| Rohan       |       2005 |                    2005 |
| Vivek       |       2009 |                    2009 |
| Chander     |       2009 |                    2009 |
| Deepak      |       2009 |                    2009 |
| Gagan Deep  |       NULL |                    2000 |
| Mohit Garg  |       NULL |                    2000 |
+-------------+------------+-------------------------+

SQL – isnull() Example, isnull() function

admin — Sat, 28 Nov 2009 09:08:45 +0000

SQL isnull() function is used find null value in rows and returns 0 (zero) on if null value found in column from database table name, otherwise if column value is not null it will return 1 value. null value will replace automatically with zero value.

SQL isnull() query example explains how to use isnull() query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       7 | Gagan Deep  | B.Tech     |       NULL |
|       8 | Mohit Garg  | M.Tech     |       NULL |
+---------+-------------+------------+------------+

isnull() examples

SELECT  Name, Year_Start, ISNULL(Year_Start) FROM class_name c;

Output

+-------------+------------+--------------------+
| Name        | Year_Start | ISNULL(Year_Start) |
+-------------+------------+--------------------+
| Amit Mishra |       2005 |                  0 |
| Robot       |       2005 |                  0 |
| Rohan       |       2005 |                  0 |
| Vivek       |       2009 |                  0 |
| Chander     |       2009 |                  0 |
| Deepak      |       2009 |                  0 |
| Gagan Deep  |       NULL |                  1 |
| Mohit Garg  |       NULL |                  1 |
+-------------+------------+--------------------+

SQL – Select distinct Example, distinct statement

admin — Sat, 28 Nov 2009 08:23:13 +0000

SQL distinct clause is used to remove duplicate rows from database table name. distinct keyword can be used on one column name and more than one column name in SQL query. distinct clause can be implemented in MySQL, oracle, db2, Microsoft SQL server.

SQL distinct query example explains how to use distinct query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       7 | Gagan Deep  | B.Tech     |       NULL |
|       8 | Mohit Garg  | M.Tech     |       NULL |
+---------+-------------+------------+------------+

syntax of SQL distinct

SELECT distinct columns FROM table_name

distinct examples

SELECT distinct Roll_No, Name, Class_Name, Year_Start FROM class_name c;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       7 | Gagan Deep  | B.Tech     |       NULL |
|       8 | Mohit Garg  | M.Tech     |       NULL |
+---------+-------------+------------+------------+

this SQL query returns all rows return because no duplicate row is found. all column name is distinct

SELECT distinct Class_Name, Year_Start FROM class_name;

Output

+------------+------------+
| Class_Name | Year_Start |
+------------+------------+
| B.Science  |       2005 |
| B.Tech     |       2005 |
| M.Tech     |       2005 |
| B.Tech     |       2009 |
| B.Science  |       2009 |
| B.Tech     |       NULL |
| M.Tech     |       NULL |
+------------+------------+

this SQL query returns those row which column name (Class_Name, Year_Start) not duplicate rows value only from table.

SELECT distinct Class_Name FROM class_name;

Output

+------------+
| Class_Name |
+------------+
| B.Science  |
| B.Tech     |
| M.Tech     |
+------------+

this SQL query check distinct on only one column name Class_Name and check duplicate rows in Class_Name column name and remove duplicate rows.

* indicates fetch all columns records from table.

SQL – Select is null Example, is not null Example

admin — Sat, 28 Nov 2009 07:52:14 +0000

SQL is null clause, is not null clause option can filter records from database table name on null value in rows. This returns only null rows which we put is null clause in query, and returns those rows which not having null in row on is not null clause. null keyword can be used on one column name and more than one column name in SQL query. null clause can be implemented in MySQL, oracle, db2, Microsoft SQL server.

SQL null query example explains how to use null query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       7 | Gagan Deep  | B.Tech     |       NULL |
|       8 | Mohit Garg  | M.Tech     |       NULL |
+---------+-------------+------------+------------+

Where clause

SELECT * FROM class_name  where Year_Start is null;

Output

+---------+------------+------------+------------+
| Roll_No | Name       | Class_Name | Year_Start |
+---------+------------+------------+------------+
|       7 | Gagan Deep | B.Tech     |       NULL |
|       8 | Mohit Garg | M.Tech     |       NULL |
+---------+------------+------------+------------+

this SQL query returns those row which column name (Year_Start) having null value only from table.

SELECT * FROM class_name  where Year_Start is not null;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
+---------+-------------+------------+------------+

this SQL query returns those row which column name (Year_Start) not having null value only from table.

* indicates fetch all columns records from table.

SQL – Select Where clause Example

admin — Sat, 28 Nov 2009 07:25:07 +0000

SQL where clause option can filter records from database table name. This returns only required rows which we put clause in query. where keyword can be used on one column name and more than one column name in SQL query. where clause can be implemented in MySQL, oracle, db2, Microsoft SQL server.

SQL select where query example explains how to use select where query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
+---------+-------------+------------+------------+

Where clause

SELECT * FROM class_name c where Year_Start = 2005;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
+---------+-------------+------------+------------+

this SQL query returns those row which column name (Year_Start) having 2005 value only from table.

select * from class_name where Year_Start > 2005;

Output

+---------+---------+------------+------------+
| Roll_No | Name    | Class_Name | Year_Start |
+---------+---------+------------+------------+
|       4 | Vivek   | B.Tech     |       2009 |
|       5 | Chander | B.Science  |       2009 |
|       6 | Deepak  | B.Science  |       2009 |
+---------+---------+------------+------------+

this SQL query returns only those row in column Year_Start greater than 2005 value only.

group by on more than one column name

SELECT * FROM class_name c
   where Year_Start= 2005 and Class_Name = 'B.Tech';

Output

+---------+-------+------------+------------+
| Roll_No | Name  | Class_Name | Year_Start |
+---------+-------+------------+------------+
|       2 | Robot | B.Tech     |       2005 |
+---------+-------+------------+------------+

this SQL query returns only those row in column Year_Start having 2005 value only and also class_name column value having B.Tech.

* indicates fetch all columns records from table.

SQL – Select Group By Example, Group by statement

admin — Sat, 28 Nov 2009 06:56:11 +0000

SQL Group by column name clause is used to give aggregate records in database table. Group by keyword is used to give records in same column rows in grouped manner. Group by can be used on one column name and more than one column name in SQL query. group by can be implemented in MySQL, oracle, db2, Microsoft SQL server.

SQL select Group by query example explains how to use select Group by query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
+---------+-------------+------------+------------+

Group by

SELECT * FROM class_name c group by Class_Name;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
+---------+-------------+------------+------------+

this SQL query returns unique column name (class_name) rows only from table.

SELECT Roll_No, Name, Class_Name, count(Class_Name)
           FROM class_name c group by Class_Name;

Output

+---------+-------------+------------+-------------------+
| Roll_No | Name        | Class_Name | count(Class_Name) |
+---------+-------------+------------+-------------------+
|       1 | Amit Mishra | B.Science  |                 3 |
|       2 | Robot       | B.Tech     |                 2 |
|       3 | Rohan       | M.Tech     |                 1 |
+---------+-------------+------------+-------------------+

this SQL query returns unique column name (class_name) rows only from table and it shows count of unique column name.

group by on more than one column name

SELECT * FROM class_name c group by Class_Name,Year_Start;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B.Science  |       2005 |
|       5 | Chander     | B.Science  |       2009 |
|       2 | Robot       | B.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       3 | Rohan       | M.Tech     |       2005 |
+---------+-------------+------------+------------+

this SQL query returns, unique column name rows only with two columns

* indicates fetch all columns records from table.

SQL – Select Order by clause keyword

admin — Tue, 24 Nov 2009 15:16:12 +0000

SQL select query is used to fetch records from database. order by column name clause is used to sorting records in database table. Order by keyword is having options for sorting data records, one is ascending sorting order, Second is descending order, it will return records in higher to lower order. In ascending sorting order, it returns records in lower to higher order. order by clause can be implemented on all database Oracle, MS Sql (Microsoft SQL), MySQL.

SQL select order by query example explains how to use select order by query in SQL.

Table class_name with all records without desired column name sorting

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B Science  |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
+---------+-------------+------------+------------+

Descending Order by Sorting

SELECT * FROM class_name c order by name desc;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       4 | Vivek       | B.Tech     |       2009 |
|       3 | Rohan       | M.Tech     |       2005 |
|       2 | Robot       | B.Tech     |       2005 |
|       6 | Deepak      | B.Science  |       2009 |
|       5 | Chander     | B.Science  |       2009 |
|       1 | Amit Mishra | B Science  |       2005 |
+---------+-------------+------------+------------+

this SQL query in sql return rows from higher to lower sorting order from table.

SELECT * FROM class_name c order by name asc;

Output

+---------+-------------+------------+------------+
| Roll_No | Name        | Class_Name | Year_Start |
+---------+-------------+------------+------------+
|       1 | Amit Mishra | B Science  |       2005 |
|       5 | Chander     | B.Science  |       2009 |
|       6 | Deepak      | B.Science  |       2009 |
|       2 | Robot       | B.Tech     |       2005 |
|       3 | Rohan       | M.Tech     |       2005 |
|       4 | Vivek       | B.Tech     |       2009 |
+---------+-------------+------------+------------+

this SQL query in sql return rows from lower to higher sorting order from table.

* indicates fetch all columns records from table.

SQL – Select with Temporary Dual table

admin — Sun, 22 Nov 2009 11:11:30 +0000

SQL select query is used to fetch records from database. Dual table is Temporary table which is created for temporary work. Dual table allow people to use from keyword in query.

SQL select dual example explains how to use select dual query in SQL.

select 3+1 from dual;

Table dual with records

+-----+
| 3+1 |
+-----+
|   4 |
+-----+

JSP, Tomcat, JDBC, Projects, Example, Program » SQL

Store Procedure in Oracle

Related Posts:

SQL Joins in Oracle

1. Equi join

2. Non Equi join

3. Outer Join

4. Self Join

5. Cross join

6. Natural join

Related Posts:

SQL – ifnull() Example, ifnull() function

Related Posts:

SQL – isnull() Example, isnull() function

Related Posts:

SQL – Select distinct Example, distinct statement

Related Posts:

SQL – Select is null Example, is not null Example

Related Posts:

SQL – Select Where clause Example

Related Posts:

SQL – Select Group By Example, Group by statement

Related Posts:

SQL – Select Order by clause keyword

Related Posts:

SQL – Select with Temporary Dual table

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