I can't able to create a select statement in oracle procedure. Please help me to create this.
Now I create the insert,update.delete statement in a procedure but i can't create a select statement. Please help me to create the select statement using cursor.
c_dbuser OUT SYS_REFCURSOR
ELSIF (TYPE_ =1) THEN
OPEN c_dbuser FOR
SELECT * FROM tbl_discount_master ;
CLOSE c_dbuser;
END IF;
call procedure_name(xx,xx,xx,1);
how can i get the selected value using call procedure statement.
In addition to the other suggestion, you have this solution when you are getting exactly one row.
DECLARE
myvar1 mytable.mycolumn1%TYPE;
myvar2 mytable.mycolumn2%TYPE;
BEGIN
SELECT mycolumn1, mycolumn2
INTO myvar1, myvar2
FROM mytable
WHERE …;
END;
This will throw an exception if there is no selected row (NO_DATA_FOUND) or if there is more than one row (TOO_MANY_ROWS).
The difference between select and the insert/update/delete is that you need to select into some structure, either one or more variables or a rowtype variable.
Avoid explicit cursors whenever possible in favour of the faster, less verbose and less error prone implicit cursor.
eg.
for cur_my_query in
select column1,
column2,
...
from ...
where ...
loop
refer here to cur_my_query or my_query.column1 etc
end loop
Related
I am new to Oracle programming (started a month ago).
I've created a cursor to retrieve a value from a table 'CDF_LU' and then use the cursor to insert into another table 'test_1'. However there is an error when I run it.
Here is my code:
DECLARE
c_cdf_table CDF_LU.PROD_COLUMN_NAME%type;
-- create cursor.
CURSOR c_CDF_Table_Name IS
SELECT PROD_COLUMN_NAME
FROM CDF_LU
ORDER BY CDF;
-- create record.
c_cdf_table c_CDF_Table_Name%ROWTYPE;
BEGIN
OPEN c_CDF_Table_Name;
LOOP
FETCH c_CDF_Table_Name INTO c_cdf_table;
EXIT WHEN c_CDF_Table_Name%NOTFOUND;
-- insert to table_1.
INSERT into test_1
select A,B,C from table_1 where some_conditions
END LOOP;
CLOSE c_CDF_Table_Name;
END;
When I run this code, there are following errors:
In line 'FETCH c_CDF_Table_Name INTO c_cdf_table;', SQL statement ignored.
In line 'FETCH c_CDF_Table_Name INTO c_cdf_table;', at most one declaration for "C_CDF_TABLE" is permitted.
In line 'INSERT into test_1', SQL statement ignored.
I wrote the SQL codes above by strictly following the syntax of cursors, so I'm not sure where the problem is.
Could you please advise? Thank you!
The way you wanted to do it is possible (of course) when errors are fixed; something like this:
declare
-- cursor
cursor c_cdf_table_name is
select prod_column_name
from cdf_lu
order by cdf;
-- cursor variable
c_cdf_table c_cdf_table_name%rowtype;
begin
open c_cdf_table_name;
loop
fetch c_cdf_table_name into c_cdf_table;
exit when c_cdf_table_name%notfound;
insert into test1 (col1, col2, co3)
select a, b, c from table1
where d = c_cdf_table.prod_column_name;
end loop;
close c_cdf_table_name;
end;
/
However, there's a way shorter & simpler option - a cursor FOR loop. As you can see, you don't have to declare a cursor variable, open the cursor, fetch from it, take care about exiting the loop nor closing the cursor - Oracle does all that for you:
begin
for cur_r in (select prod_column_name
from cdf_lu
order by cdf)
loop
insert into test1 (col1, col2, co3)
select a, b, c from table1
where d = c_cdf_table.prod_column_name;
end loop;
end;
/
I have a simple test function where I'm passing in a specific ID (the primary key of the table I'm selecting from), and computing a simple function on it and the parameters.
The skeleton code and test:
create or replace function test(id varchar2, area float) return float is
theRow forest%ROWTYPE;
begin
select * into theRow from forest where Forest_No = id;
return area / theRow.Area;
end;
begin
select test('1', 16000) from dual;
end;
The output:
[2019-10-14 21:19:10] [65000][6550] ORA-06550: line 2, column 5:
[2019-10-14 21:19:10] PLS-00428: an INTO clause is expected in this SELECT statement
I am at a loss for what to do here, as far as I can tell the documentation and examples use the same order and syntax. I have tried moving the into clause to the end as in Postgresql, but that did not work.
What have I missed here?
Issue is in calling statement.
Whenever select statement is used in plsql block it must have into clause to assign return value to variable.
You should remove begin and end from your calling code:
--begin -- remove this
select test('1', 16000) from dual;
--end; -- remove this
Or if you want to use it in plsql block then add into clause:
Declare
Area_ float(precision);
begin
select test('1', 16000) into area_ from dual;
-- use area_ in your code wherever required
dbms_output.put_line('area: ' || area_);
end;
Cheers!!
Is it possible to select the parameters for calling a procedure from the select statement?
EXECUTE PROCEDURE_NAME(para1,para2,para3,para4);
commit;
Is it possible to select para1,para2,para3,para4 from a select query?
EXECUTE PROCEDURE_NAME((SELECT PARA1,PARA2,PARA3,PARA4 FROM TABLEA))
COMMIT;
I do not have access to modify the procedure.
As a slight variation on what #vc74 suggested, you could just replace your EXECUTE command (which, assuming this is SQL*Plus or SQL Developer anyway, is just a wrapper for an anonymous block anyway) with an explicit anonymous block:
begin
for r in (SELECT PARA1,PARA2,PARA3,PARA4 FROM TABLEA) loop
PROCEDURE_NAME(r.PARA1,r.PARA2,r.PARA3,r.PARA4);
end loop;
end;
/
(I've left the bits from your original call uppercase and the new bits lower case mostly to distinguish them.)
Using a loop just means you don't need to declare local variables and select into those. It would also allow you to process multiple rows from the table, though I see form a comment you only expect one row. However, the flip side of that is it won't complain if there are no rows, or if there is more than one row, as the variable approach would do.
You could also use a record type to avoid declaring all the parameters separately:
declare
l_row tablea%rowtype;
begin
SELECT * into l_row FROM TABLEA;
PROCEDURE_NAME(l_row.PARA1,l_row.PARA2,l_row.PARA3,l_row.PARA4);
end;
/
This now does expect exactly one row to be found in the table.
You can call the functions in sql. So if you are able to create a function in your schema then you can do the following:
create a function function_name in your schema that calls the procedure procedure_name and returns some dummy result
use this function in sql query: select function_name(para1,para2,para3,para4) from tablea
example of function:
create or replace function function_name(
p1 varchar2,
p2 varchra2,
p3 varchar2,
p4 varchar2
) return number
is
begin
procedure_name(p1,p2,p3,p4); -- here you execute the procedure
return null;
end;
In SQL Server we can use this:
DECLARE #variable INT;
SELECT #variable= mycolumn from myTable;
How can I do the same in Oracle? I'm currently attempting the following:
DECLARE COMPID VARCHAR2(20);
SELECT companyid INTO COMPID from app where appid='90' and rownum=1;
Why this is not working?
SELECT INTO
DECLARE
the_variable NUMBER;
BEGIN
SELECT my_column INTO the_variable FROM my_table;
END;
Make sure that the query only returns a single row:
By default, a SELECT INTO statement must return only one row. Otherwise, PL/SQL raises the predefined exception TOO_MANY_ROWS and the values of the variables in the INTO clause are undefined. Make sure your WHERE clause is specific enough to only match one row
If no rows are returned, PL/SQL raises NO_DATA_FOUND. You can guard against this exception by selecting the result of an aggregate function, such as COUNT(*) or AVG(), where practical. These functions are guaranteed to return a single value, even if no rows match the condition.
A SELECT ... BULK COLLECT INTO statement can return multiple rows. You must set up collection variables to hold the results. You can declare associative arrays or nested tables that grow as needed to hold the entire result set.
The implicit cursor SQL and its attributes %NOTFOUND, %FOUND, %ROWCOUNT, and %ISOPEN provide information about the execution of a SELECT INTO statement.
Not entirely sure what you are after but in PL/SQL you would simply
DECLARE
v_variable INTEGER;
BEGIN
SELECT mycolumn
INTO v_variable
FROM myTable;
END;
Ollie.
One Additional point:
When you are converting from tsql to plsql you have to worry about no_data_found exception
DECLARE
v_var NUMBER;
BEGIN
SELECT clmn INTO v_var FROM tbl;
Exception when no_data_found then v_var := null; --what ever handle the exception.
END;
In tsql if no data found then the variable will be null but no exception
ORA-01422: exact fetch returns more than requested number of rows
if you don't specify the exact record by using where condition, you will get the above exception
DECLARE
ID NUMBER;
BEGIN
select eid into id from employee where salary=26500;
DBMS_OUTPUT.PUT_LINE(ID);
END;
For storing a single row output into a variable from the select into query :
declare v_username varchare(20);
SELECT username into v_username FROM users WHERE user_id = '7';
this will store the value of a single record into the variable v_username.
For storing multiple rows output into a variable from the select into query :
you have to use listagg function. listagg concatenate the resultant rows of a coloumn into a single coloumn and also to differentiate them you can use a special symbol.
use the query as below
SELECT listagg(username || ',' ) within group (order by username) into v_username FROM users;
I am fairly new to oracle and need to solve the following problem.
inside a stored proc I want to return 2 cursors like this.
PROCEDURE MyProcA()
as
begin
open refcursorA FOR
select id, ..... FROM tableA where ..... long series of conditions
open refcursorB FOR
select * FROM table b where b.id IN (select id FROM tableA where ..... long series of conditions)
This is how I have the stored proc at the moment but I don't like the repetition. The where clause SQL in the parentheses in the 2nd cursor is exactly the same the first cursor. How can I load it into a temp table or associative array or something to use in both cursors.
Thanks in advance
It seems like you need REF Cursor
How to declare ?
cursor cursor_name is ref cursor;
How to use it ?
open cursor_name for your select query
loop
fetch cursor_name into some_variable;
exit when cursor_name%notfound;
do_something;
end loop;
close cursor_name;
So, same cursor variable will point to different sql area dynamically.
OR
You can see Cursor Expression