I have this table :
| Pattern |
----------------------
|category |varchar|
|patternexpr |varchar|
For example in this table I can have a category ISBN and its pattern to recognize it.
I want to create a procedure which takes three arguments : a table T, one of its column C and a category. I want to print every rows in column C in T table which respect the pattern associated.
This is what I did (Updated with the correct answer):
CREATE OR REPLACE PROCEDURE Recognize(T varchar,C varchar,catego varchar)
IS
v_patt Pattern.CATEGOR%Type;
BEGIN
SELECT patternexpr INTO v_patt
FROM Pattern WHERE CATEGOR=catego;
FOR myrow IN (SELECT C FROM T WHERE REGEXP_LIKE(C, v_patt) LOOP
dbms_output.put_line(myrow.C);
END LOOP;
END;
/
How can I declare a cursor to print my result without knowing the value of my variable patt in the "DECLARE" place ? Should I add another declare and begin...end bloc after the first query ? What is the best way to do it ?
(I'm working on Oracle SGBD)
Use REF CURSOR to fetch records for this purpose.
CREATE OR REPLACE PROCEDURE Recognize(
T VARCHAR2,
C VARCHAR2,
catego VARCHAR2)
IS
v_patt Pattern.CATEGOR%Type;
v_cur_txt VARCHAR2(400);
TYPE cur_type
IS
REF
CURSOR;
v_cur cur_type;
v_c VARCHAR2(20);
BEGIN
SELECT patternexpr INTO v_patt FROM Pattern WHERE CATEGOR=catego;
v_cur_txt := 'SELECT '||C||' FROM '|| T ||' WHERE REGEXP_LIKE('||C||', '''||v_patt||''')';
OPEN v_cur FOR v_cur_txt;
LOOP
FETCH v_cur INTO v_c;
EXIT
WHEN v_cur%NOTFOUND;
DBMS_OUTPUT.PUT_LINE(v_c);
END LOOP;
CLOSE v_cur;
END;
/
NOTE: : Include proper EXCEPTION handling in your code for NO_DATA_FOUND etc.Also as per Nicholas , make some validations by using dbms_assert package
In Oracle, you don't need an explicit cursor:
for myrow in (select c from t where regexp_like(c, patt) loop
dbms_output.put_line(myrow.c);
end loop;
I would call the pattern variable something like v_patt; that way, declared variables don't get confused with column names.
Related
table :
create table emp
(
E_ID number,
E_NAME varchar2(30)
);
select * from emp;
101 name1
102 name2
My code:
declare
v1 varchar2(30) := '101,102';
begin
for i in (select e_id,e_name
from emp
where e_id in (v1)) loop
dbms_output.put_line(i.e_id);
end loop;
end;
/
ISSUE:
Getting ORA -01722:invalid number
Please help to understand this issue and suggest me the solution.
It is syntax error.
E_ID is of number type and you are comparing it will v1 which is varchar2 type.
Welcome to SO. A great place to ask questions: I can see what you're trying to do. Syntactically, you'd be forgiven for trying to query your table using the "IN" clause, but as others have said, this can not be done where you have committed your numeric values into a varchar2. In anycase, an array or a collection, (even if you had created one) it isn't an easy option here. But you do have a variety of solutions open to you:
1/ Place your numbers into an Array and use a condition in your loop and check that e_id forms part of the your array. But in-elegant!
2/ Create a global temporary table and add your numbers in and add the table into your query, specify a join.
3/ Create some dynamic PL/SQL using a Ref Cursor. I've included an example for you below, using your table (emp) and values. In this case, you'd be able to build up your string according to the values you want to query. See below. The varchar2 string: sqlString can be manipulated however you want. Paste into a test-harness and see. Hope it helps
declare
type refCursor is ref cursor;
tableCursor refCursor;
emp_record emp%rowtype;
sqlString varchar2(200);
begin
-- Dynamic SQL statement with placeholder:
sqlString := 'SELECT * FROM emp WHERE e_id in
(101, 102)';
-- Open cursor:
open tableCursor for sqlString;
-- Fetch rows from result set one at a time:
loop
fetch tableCursor
into emp;
exit when tableCursor%notfound;
dbms_output.put_line(emp.e_id);
end loop;
-- Close cursor:
close tableCursor;
end;
Does anyone know how to use their tables and columns from pre-existing databases in a pl/sql command. I am using something from Oracles webpage to use as an example.
SQL> declare
2 v_line varchar2(40):= '&v_string';
3 begin
4 v_line := 'Hello '||v_line;
5 dbms_output.put_line (v_line);
6 end;
7 /
old 2: v_line varchar2(40):= '&v_string';
New 2: v_line varchar2(40):= 'Thomas';
Hello Thomas
PL/SQL procedure successfully completed.
I am wanting to be able to manipulate the data from above. Lets say I have a table called name_s and I have columns called n_first and n_last and I want to use those columns to output 'Hello Thomas' but using those tables.
I am new to pl.sql and trying to learn the syntax.
I wasn't sure if you could,
DECLARE
n_first
n_last
BEGIN
SELECT * FROM name_s
n_fisrt := 'Thomas'||n_first;
dbms_output.put_line(n_first)
END;
/
Desired Output: 'Thomas'
I understand that this is not syntactically correct but I am just trying to pick up on how you can use data from your existing tables to get this sort of desired output
EDIT: The above table is hypothetical and only contains two columns for this example. Now using real tables and data.
SET SERVEROUTPUT ON;
begin
for cur_r in (select loc_t from loc_t_matrix where store_s in(1,2,3,4,5); loop
dbms_output.put_line('Hello store' || cur_r.loc_traits );
end loop;
end;
/
The above does not compile
Do you need something like this
declare
v_authName author.author_last_name%type;
begin
select
author_last_name into v_authName
from
author
where
author_key = 'A103';
dbms_output.put_line('Name: '||v_authName);
end;
/
Name: weaton
http://www.dba-oracle.com/t_pl_sql_plsql_select_into_clause.htm
As tables usually contain more than one row, I presume that NAME_S also contains several rows. In that case, the simplest option to display those names is a cursor FOR loop (Google for it). For example:
begin
for cur_r in (select n_first, n_last from name_s) loop
dbms_output.put_line('Hello ' || cur_r.n_first ||' '||cur_r.n_last);
end loop;
end;
/
As you can see, you don't need local variables in that case.
If you used your SELECT ... INTO (as suggested by mCeviker), that would work unless it raises TOO-MANY-ROWS (as you can't put all rows' names into a single variable).
I have a cursor c2, with one column 'note', containing numbers.
I want to check, whether the column contains 5 and change my local variable if so.
this:
CREATE OR REPLACE PROCEDURE proc
IS
result varchar(50);
cursor c2 is
SELECT note
FROM student;
BEGIN
IF c2.note IN(5) THEN
result := 'contains 5';
DBMS_OUTPUT.PUT_LINE(result);
END;
/
doesnt work.
please help!
In your code, you're declaring a cursor but you are never opening it and never fetching data from it. You'd need, presumably, some sort of loop to iterate through the rows that the cursor returned. You'll either need to explicitly or implicitly declare a record into which each particular row is fetched. One option to do that is something like
CREATE OR REPLACE PROCEDURE proc
IS
result varchar(50);
cursor c2 is
SELECT note
FROM student;
BEGIN
FOR rec IN c2
LOOP
IF rec.note IN(5) THEN
result := 'contains 5';
DBMS_OUTPUT.PUT_LINE(result);
END IF;
END LOOP;
END;
/
Note that you also have to have an END IF that corresponds to your IF statement. Naming a cursor c2 is also generally a bad idea-- your variables really ought to be named meaningfully.
You have too loop over the records/rows returned in the cursor; you can't refer to the cursor itself like that:
CREATE OR REPLACE PROCEDURE proc
IS
result varchar(50);
cursor c2 is
SELECT note
FROM student;
BEGIN
FOR r2 IN c2 LOOP
IF r2.note = 5 THEN -- IN would also work but doesn't add anything
result := 'contains 5';
END IF;
END LOOP;
DBMS_OUTPUT.PUT_LINE(result);
END;
/
But if you're just testing for the existence of any record with value 5 then you don't need a cursor:
CREATE OR REPLACE PROCEDURE proc
IS
result varchar(50);
BEGIN
SELECT max('contains 5')
INTO result
FROM student
WHERE note = 5;
DBMS_OUTPUT.PUT_LINE(result);
END;
/
If there are any rows with five you'll get the 'contains 5' string; if not you'll get null. The max() stops an exception being thrown if there are either zero or more than one matching records in the table.
You are missing an END IF and need to LOOP over the cursor. The procedure name is included in the final END.
But using IN should work. Like this:
CREATE OR REPLACE PROCEDURE proc
IS
result varchar(50);
cursor c2 is
SELECT note
FROM student;
BEGIN
FOR rec in c2
LOOP
IF rec.note IN (5) THEN
result := 'contains 5';
END IF;
END LOOP;
DBMS_OUTPUT.PUT_LINE(result);
END proc;
/
I have the following problem. I am an experienced Java programmer but am a bit of a n00b at SQL and PL/SQL.
I need to do the following.
1 Pass in a few arrays and some other variables into a procedure
2 Loop on the values in the arrays (they all have the same number of items) and dynamically create an SQL statement
3 Run this statement and add it to the result set (which is an OUT parameter of the procedure)
I already have experience of creating an SQL query on the fly, running it and adding the result to a result set (which is a REF CURSOR) but I'm not sure how I'd loop and add the results of each call to the query to the same result set. I'm not even sure if this is possible.
Here's what I have so far (code edited for simplicity). I know it's wrong because I'm just replacing the contents of the RESULT_SET with the most recent query result (and this is being confirmed in the Java which is calling this procedure).
Any and all help would be greatly appreciated.
TYPE REF_CURSOR IS REF CURSOR;
PROCEDURE GET_DATA_FASTER(in_seq_numbers IN seq_numbers_array, in_values IN text_array, in_items IN text_array, list IN VARCHAR2, RESULT_SET OUT REF_CURSOR) AS
query_str VARCHAR2(4000);
seq_number NUMBER;
the_value VARCHAR2(10);
the_item VARCHAR2(10);
BEGIN
FOR i IN 1..in_seq_numbers.COUNT
LOOP
seq_number := in_seq_numbers(i);
the_value := trim(in_values(i));
the_item := trim(in_items(i));
query_str := 'SELECT distinct '||seq_number||' as seq, value, item
FROM my_table ai';
query_str := query_str || '
WHERE ai.value = '''||the_value||''' AND ai.item = '''||the_item||'''
AND ai.param = ''BOOK''
AND ai.prod in (' || list || ');
OPEN RESULT_SET FOR query_str;
END LOOP;
EXCEPTION WHEN OTHERS THEN
RAISE;
END GET_DATA_FASTER;
A pipelined table function seems a better fit for what you want, especially if all you're doing is retrieving data. See http://www.oracle-base.com/articles/misc/pipelined-table-functions.php
What you do is create a type for your output row. So in your case you would create an object such as
CREATE TYPE get_data_faster_row AS OBJECT(
seq NUMBER(15,2),
value VARCHAR2(10),
item VARCHAR2(10)
);
Then create a table type which is a table made up of your row type above
CREATE TYPE get_data_faster_data IS TABLE OF get_data_faster_row;
Then create your table function that returns the data in a pipelined manner. Pipelined in Oracle is a bit like a yield return in .net (not sure if you're familiar with that). You find all of the rows that you want and "pipe" them out one at a time in a loop. When your function completes the table that's returned consists of all the rows you piped out.
CREATE FUNCTION Get_Data_Faster(params) RETURN get_data_faster_data PIPELINED AS
BEGIN
-- Iterate through your parameters
--Iterate through the results of the select using
-- the current parameters. You'll probably need a
-- cursor for this
PIPE ROW(get_data_faster_row(seq, value, item));
LOOP;
LOOP;
END;
EDIT: Following Alex's comment below, you need something like this. I haven't been able to test this but it should get you started:
CREATE FUNCTION Get_Data_Faster(in_seq_numbers IN seq_numbers_array, in_values IN text_array, in_items IN text_array, list IN VARCHAR2) RETURN get_data_faster_data PIPELINED AS
TYPE r_cursor IS REF CURSOR;
query_results r_cursor;
results_out get_data_faster_row := get_data_faster_row(NULL, NULL, NULL);
query_str VARCHAR2(4000);
seq_number NUMBER;
the_value VARCHAR2(10);
the_item VARCHAR2(10);
BEGIN
FOR i IN 1..in_seq_number.COUNT
LOOP
seq_number := in_seq_numbers(i);
the_value := trim(in_values(i));
the_item := trim(in_items(i));
query_str := 'SELECT distinct '||seq_number||' as seq, value, item
FROM my_table ai';
query_str := query_str || '
WHERE ai.value = '''||the_value||''' AND ai.item = '''||the_item||'''
AND ai.param = ''BOOK''
AND ai.prod in (' || list || ');
OPEN query_results FOR query_str;
LOOP
FETCH query_results INTO
results_out.seq,
results_out.value,
results_out.item;
EXIT WHEN query_results%NOTFOUND;
PIPE ROW(results_out);
END LOOP;
CLOSE query_results;
END LOOP;
END;
Extra info from Alex's comment below useful for the answer:
you can have multiple loops from different sources, and as long as the
data from each be put into the same object type, you can just keep
pumping them out with pipe row statements anywhere in the function.
The caller sees them as a table with the rows in the order you pipe
them. Rather than call a procedure and get a result set as an output
parameter, you can query as select seq, value, item from
table(package.get_data_faster(a, b, c, d)), and of course you can
still have an order by clause if the order they're piped isn't what
you want.
I need to return a cursor from Oracle procedure, the cursor has to contain RECORD types. I know how to solve this problem when the RECORD is simple, but how can this be solved for NESTED RECORDS?
There is a working block of code for simple RECORD:
-- create package with a RECORD type
create or replace package pkg as
-- a record contains only one simple attribute
type t_rec is RECORD (
simple_attr number
);
end;
/
-- create a testing procedure
-- it returns a cursor populated with pkg.t_rec records
create or replace procedure test_it(ret OUT SYS_REFCURSOR) is
type cur_t is ref cursor return pkg.t_rec;
cur cur_t;
begin
-- this is critical; it is easy to populate simple RECORD type,
-- because select result is mapped transparently to the RECORD elements
open cur for select 1 from dual;
ret := cur; -- assign the cursor to the OUT parameter
end;
/
-- and now test it
-- it will print one number (1) to the output
declare
refcur SYS_REFCURSOR;
r pkg.t_rec;
begin
-- call a procedure to initialize cursor
test_it(refcur);
-- print out cursor elements
loop
fetch refcur into r;
exit when refcur%notfound;
dbms_output.put_line(r.simple_attr);
end loop;
close refcur;
end;
/
Can you show me, how it could be done when a RECORD t_rec contains NESTED RECORD?
Modify the example in the folowing way:
-- create package with a NESTED RECORD type
create or replace package pkg as
type t_rec_nested is RECORD (
nested_attr number
);
-- a record with NESTED RECORD
type t_rec is RECORD (
simple_attr number,
nested_rec t_rec_nested
);
end;
/
create or replace procedure test_it(ret OUT SYS_REFCURSOR) is
type cur_t is ref cursor return pkg.t_rec;
cur cur_t;
begin
-- how to populate a result?
open cur for ????
ret := cur;
end;
/
The question is how to modify test_it procedure to populate a cursor?
I spent many hours searching the solution, I will appreciate any help.
I don't think it's possible as you have it, as RECORDs are a PL/SQL data type. You can do an equivalent thing by making an OBJECT. If you scroll down to the bottom of this link (or search for "Updating a Row Using a Record Containing an Object: Example" on the page), you will see how that is handled.