My first PL/SQL block not working with using Select query within begin

Question

I am new to PL/SQL , just started with basics of BLOCKS .
I am having a query here in executing a block .
When i am doing a insert oprtation in Blocks Begin method everything is working fine , but when ever i tried to do select operation , some error is being thrown .
First of all This is my Table :
select from try :*
KEY      VALUE
Key     Value
Key1     Value1
Key2     Value2
Key3     Value3
======================
This is the code which is not working : Please see the code and tell me what is the problem .
DECLARE
v_KEY    VARCHAR2(20);
v_VALUE   VARCHAR2(20);
BEGIN
select key into v_KEY FROM try where v_value='Value' ;
dbms_output.put_line(v_KEY);
END;
When i run this code , it is saying Data Not Found on this line " select key into v_KEY FROM try where v_value='Value' ;"
wheer when i run tis individually it worked fine :
select KEY FROM try where VALUE='Value' ;"
please share your ideas .as why it isn't running ??
Edited by: user10503747 on Sep 20, 2010 3:16 AM

Answer 1

Hi,
user10503747 wrote:
I am new to PL/SQL , just started with basics of BLOCKS .
I am having a query here in executing a block .
When i am doing a insert oprtation in Blocks Begin method everything is working fine , but when ever i tried to do select operation , some error is being thrown .
First of all This is my Table :
select from try :*
KEY      VALUE
Key     Value
Key1     Value1
Key2     Value2
Key3     Value3
======================
This is the code which is not working : Please see the code and tell me what is the problem .
DECLARE
v_KEY    VARCHAR2(20);
v_VALUE   VARCHAR2(20);
BEGIN
select key into v_KEY FROM try where v_value='Value' ;
dbms_output.put_line(v_KEY);
END;
When i run this code , it is saying Data Not Found on this line " select key into v_KEY FROM try where v_value='Value' ;"
wheer when i run tis individually it worked fine :
select KEY FROM try where VALUE='Value' ;"
please share your ideas .as why it isn't running ??
Edited by: user10503747 on Sep 20, 2010 3:16 AMInstead of:
{code}
select key into v_KEY FROM try where v_value='Value' ;
{code}
perhaps you meant something like:
{code}
v_value := 'Value1';
select key into v_KEY FROM try where v_value=Value ; -- No quotes
{code}
Until you assign a vlue to a variable, like v_value, it is NULL, so your original statement was equivalent to
{code}
select KEY FROM try where NULL='Value' ;
{code}
In PL/SQL, a SELECT ... INTO statement must return exactly one row, or else you will get an error (either NO_DATA_FOUND or TOO_MANY_ROWS). This is different from SQL, where a query cn return any number of rows, including 0, without raising an error.