For debugging purposes, I'd like to be able to "TO_CHAR" an Oracle PL/SQL in-memory table. Here's a simplified example, of what I'd like to do:
DECLARE
TYPE T IS TABLE OF MY_TABLE%ROWTYPE INDEX BY PLS_INTEGER;
V T;
BEGIN
-- ..
-- Here, I'd like to dbms_output V's contents, which of course doesn't compile
FOR i IN V.FIRST .. V.LAST LOOP
dbms_output.put_line(V(i));
END LOOP;
-- I want to omit doing this:
FOR i IN V.FIRST .. V.LAST LOOP
dbms_output.put_line(V(i).ID || ',' || V(i).AMOUNT ...);
END LOOP;
END;
Can this be achieved, simply? The reason I ask is because I'm too lazy to write this debugging code again and again, and I'd like to use it with any table type.
ok, sorry this isn't complete, but to followup with #Lukas, here's what I have so far:
First, instead of trying to create anydata/anytype types, I tried using XML extracted from a cursor...weird, but its generic:
CREATE OR REPLACE procedure printCur(in_cursor IN sys_refcursor) IS
begin
FOR c IN (SELECT ROWNUM rn,
t2.COLUMN_VALUE.getrootelement () NAME,
EXTRACTVALUE (t2.COLUMN_VALUE, 'node()') VALUE
FROM TABLE (XMLSEQUENCE (in_cursor)) t,
TABLE (XMLSEQUENCE (EXTRACT (COLUMN_VALUE, '/ROW/node()'))) t2
order by 1)
LOOP
DBMS_OUTPUT.put_line (c.NAME || ': ' || c.VALUE);
END LOOP;
exception
when others then raise;
end;
/
Now, to call it, you need a cursor, so I tried casting to cursor in pl/sql, something like:
open v_cur for select * from table(cast(v_tab as tab_type));
But depending on how v_tab is defined, this may or may not cause issues in pl/sql cast (using %rowtype in nested table def seems to give issues).
Anyway, you can build on this or refine it as you like. (and possibly use xmltable...)
Hope that helps
Related
Is there a way to set schema name as variable in oracle procedure?
create or replace procedure test is
v_schema varchar2(30);
begin
insert into v_schema.tab_a ( a, b)
select (a, b) from xyz;
end;
/
Thanks
You'd need to resort to dynamic SQL
create or replace procedure test
is
v_schema varchar2(30);
v_sql varchar2(1000);
begin
v_sql := 'insert into ' || v_schema || '.tab_a( a, b ) ' ||
'select a, b from xyz';
dbms_output.put_line( 'About to execute the statement ' || v_sql );
execute immediate v_sql;
end;
A couple of points
You almost certainly want to build the SQL statement in a local variable that you can print out and/or log before executing it. Otherwise, when there are syntax errors, you're going to have a much harder time debugging.
You almost never want to resort to dynamic SQL in the first place. The fact that you have a procedure where you know you want to insert all the rows from xyz into a table named tab_a but you don't know which schema that table is in is a red flag. That's unusual and often indicates a problem with your design. Very, very occasionally dynamic SQL is a wonderful tool when you need extra flexibility. But more often than not when you're thinking about a problem and dynamic SQL is the answer you want to reconsider the problem.
I want to create procedure, that will use cursor, which is the same for arbitrary tables. My current one looks like this:
create or replace
PROCEDURE
some_name(
p_talbe_name IN VARCHAR2,
p_chunk_size IN NUMBER,
p_row_limit IN NUMBER
) AS
CURSOR v_cur IS
SELECT common_column,
ora_hash(substr(common_column, 1, 15), p_chunk_size) as chunk_number
-- Here it can find the table!
FROM p_table_name;
TYPE t_sample IS TALBE OF v_cur%rowtype;
v_sample t_sample;
BEGIN
OPEN v_cur;
LOOP FETCH v_cur BULK COLLECT INTO v_sample LIMIT p_row_limit;
FORALL i IN v_sample.first .. v_sample.last
INSERT INTO chunks VALUES v_sample(i);
COMMIT;
EXIT WHEN v_cur%notfound;
END LOOP;
CLOSE v_cur;
END;
The problem is that it cannot find the table named p_table_name which I want to parametrize. The thing is that I need to create chunks based on hashes for common_column which exists in all intended tables. How to deal with that problem? Maybe there is the equivalent oracle code that will do the same thing? Then I need the same efficiency for the query. Thanks!
I would do this as a single insert-as-select statement, complicated only by the fact you're passing in the table_name, so we need to use dynamic sql.
I would do it something like:
CREATE OR REPLACE PROCEDURE some_name(p_table_name IN VARCHAR2,
p_chunk_size IN NUMBER,
p_row_limit IN NUMBER) AS
v_table_name VARCHAR2(32); -- 30 characters for the tablename, 2 for doublequotes in case of case sensitive names, e.g. "table_name"
v_insert_sql CLOB;
BEGIN
-- Sanitise the passed in table_name, to ensure it meets the rules for being an identifier name. This is to avoid SQL injection in the dynamic SQL
-- statement we'll be using later.
v_table_name := DBMS_ASSERT.ENQUOTE_LITERAL(p_table_name);
v_insert_sql := 'insert into chunks (common_column_name, chunk_number)'||CHR(10)|| -- replace the column names with the actual names of your chunks table columns.
'select common_column,'||CHR(10)||
' ora_hash(substr(common_column, 1, 15), :p_chunk_size) AS chunk_number'||CHR(10)||
'from '||v_table_name||CHR(10)||
'where rownum <= :p_row_limit';
-- Used for debug purposes, so you can see the definition of the statement that's going to be run.
-- Remove before putting the code in production / convert to proper logging code:
dbms_output.put_line(v_insert_sql);
-- Now run the statement:
EXECUTE IMMEDIATE v_insert_sql USING p_chunk_size, p_row_limit;
-- I've included the p_row_limit in the above statement, since I'm not sure if your original code loops through all the rows once it processes the
-- first p_row_limit rows. If you need to insert all rows from the p_table_name into the chunks table, remove the predicate from the insert sql and the extra bind variable passed into the execute immediate.
END some_name;
/
By using a single insert-as-select statement, you are using the most efficient way of doing the work. Doing the bulk collect (which you were using) would use up memory (storing the data in the array) and cause extra context switches between the PL/SQL and SQL engines that the insert-as-select statement avoids.
I created a procedure to calculate the hashcode of a record (complete line of a table) and then update a column with the calculated hashcode number.
Here's my code at this point (which is based on some info I manage to gather from Google):
CREATE OR REPLACE PROCEDURE calcHashCode (inputTableString IN varchar2) IS
c_data varchar2(3000); --QUERY
c_cursor sys_refcursor; --CURSOR
c_record inputTableString%rowtype; -- Problem is here
BEGIN
c_data := 'SELECT * FROM ' || inputTableString;
OPEN c_cursor for c_data;
LOOP
FETCH c_cursor INTO c_record;
EXIT WHEN c_cursor%notfound;
-- will do stuff here with the records
dbms_output.put_line('stuff');
END LOOP;
CLOSE c_cursor;
END;
/
SHOW ERRORS
4/13 PLS-00310: with %ROWTYPE attribute, 'INPUTTABELA' must name a table, cursor or cursor-variable
4/13 PL/SQL: Item ignored
11/25 PLS-00320: the declaration of the type of this expression is incomplete or malformed
11/5 PL/SQL: SQL Statement ignored
So, my idea (for the final stage of the procedure) is to iterate through out the records, build a string with and then calculate the hashcode. After that, I'll run the update instruction.
The thing is at this point using a varchar as an argument and I'm not being able to iterate through the table in order to get my concatenate records.
dynamic cursors are the ugliest...
the problem is with that section:
c_data varchar2(3000); --QUERY
c_cursor sys_refcursor; --CURSOR
c_record inputTableString%rowtype;
i used something like this:
TYPE t_data IS REF CURSOR;
cr_data t_data;
cr_data_rec inputTableString%ROWTYPE; --that table need to be exists in compile time
the rest are good i think
Have you considered pushing the whole declaration and loop into an anonymous block that will then get executed by EXECUTE IMMEDIATE? You can then simplify your looping construct to a simple FOR loop too.
I'm away from my database at the moment, so excuse any syntax glitches, but something like
CREATE OR REPLACE PROCEDURE calcHashCode (inputTableString IN varchar2) IS
c_data varchar2(30000); --QUERY
BEGIN
c_data := '
BEGIN
FOR aRec IN
(SELECT * FROM ' || inputTableString ||' )
LOOP
--do your stuff
END LOOP;
END';
execute immediate c_Data;
END;
/
It may not be pretty, and your "Stuff" may not easily be able to be fit into this construct, but it IS feasible
You can do all this kind of stuff with PL/SQL package DBMS_SQL, however it is definitely not for beginners and you should start with something easier.
Examples for DBMS_SQL
Is there any rowid like facility in a pl-sql collection? In my case, while I am using this collection in an sql query, I also need the sequence number as they are put in. I know modification is data struecture is a way, but I want to use the index of the collection. so what I am looking for is something like this:
TYPE t_List IS TABLE OF VARCHAR2(200);
and
declare
v_Data t_List := t_List('data 1'
,'data_2'
,'data3');
......
FOR Rec IN (SELECT Column_Value v
,ROWID r
FROM TABLE(CAST(v_data t_list)))
LOOP
Dbms_Output.Put_Line('at ' || Rec.r || ':' || Rec.v);
-- .... and other codes here
END LOOP;
The loop is not expected to be executed in sequence, but I want something built-in like ROWID that is like the index of the collection.
Only schema-level types can be used in SQl statement, even within a PL/SQL block. As you seem to suggest you already know, you can create your own object type that includes the 'sequence' ID:
CREATE TYPE t_object AS OBJECT (
id NUMBER,
data VARCHAR2(200)
)
/
And a collection of that type:
CREATE TYPE t_List IS TABLE OF t_object;
/
And then populate the ID as you build the list:
DECLARE
l_List t_List := t_List(t_object(1, 'data 1')
,t_object(2, 'data_2')
,t_object(3, 'data3'));
BEGIN
FOR Rec IN (SELECT id, data
FROM TABLE(l_list))
LOOP
Dbms_Output.Put_Line('at ' || Rec.id || ':' || Rec.data);
-- .... and other codes here
END LOOP;
END;
/
Without an object type you can use the ROWNUM pseudocolumn:
CREATE TYPE t_List IS TABLE OF VARCHAR2(200);
/
DECLARE
v_Data t_List := t_List('data 1'
,'data_2'
,'data3');
BEGIN
FOR Rec IN (SELECT Column_Value v
,ROWNUM r
FROM TABLE(v_data))
LOOP
Dbms_Output.Put_Line('at ' || Rec.r || ':' || Rec.v);
-- .... and other codes here
END LOOP;
END;
/
anonymous block completed
at 1:data 1
at 2:data_2
at 3:data3
As far as I'm aware that isn't guaranteed to preserve the original creation sequence. I think it almost certainly will at the moment, but perhaps isn't something you should rely on as always being true. (There is no order without an order by, but here you don't have anything you can order by without destroying your initial order...).
If you query a subset of the table - I'm not sure what you mean by "the loop is not expected to be executed in sequence" - you'd need to generate the ROWNUM in a subquery before filtering or it won't be consistent. You'd also need to generate the ROWNUM in a subquery if you're joining this to other, real, tables - I imagine you are, otherwise you could use a PL/SQL collection.
If indexing is important, use Associative Arrays(Also known as Index-by tables)
Refer his.
I'm trying to use an array of input values to my procedure in an IN Clause as part of the where clause of a cursor. I know that this has been asked before, but I haven't seen how to make my syntax compile correctly.
In the package specification, the type is
TYPE t_brth_dt IS TABLE OF sourceTable.stdt_brth_dt%TYPE INDEX BY PLS_INTEGER;
sourceTable.std_brth_dt is a date column in the table.
Simplified version of my cursor is in the package body is -
cursor DataCursor_Sort( p_brth_dt in t_brth_dt) is
SELECT *
FROM sourceTable
WHERE a.brth_dt IN (select column_value
from table(p_brth_dt))
When I try to compile this, I'm getting the following errors.
[1]:(Error): PLS-00382: expression is of wrong type
[2]:(Error): PL/SQL: ORA-22905: cannot access rows from a non-nested table item
I know this looks similar to other questions, but I don't understand what the syntax error is.
In order to use collection defined as a nested table or an associative array in the from clause of a query you either should, as #Alex Poole correctly pointed out, create a schema level (SQL) type or use one, that is available to you trough ODCIConst package - odcidatelist as you intend to use a list of dates. For example, your cursor definition might look like this:
cursor DataCursor_Sort(p_brth_dt in sys.odcidatelist) is
select *
from sourceTable
where a.brth_dt IN (select column_value
from table(p_brth_dt))
OR
cursor DataCursor_Sort(p_brth_dt in sys.odcidatelist) is
select s.*
from sourceTable s
join table(p_brth_dt) t
on (s.brth_dt = t.column_value)
Note: You should take into consideration the time part of a date when performing a date comparison. If you want to compare date part only it probably would be useful to get rid of time part by using trunc() function.
It is possible to use a PL/SQL-defined nested table type (as opposed to a SQL-defined nested table type) indirectly in an IN clause of a SELECT statement in a PL/SQL package. You must use a PIPELINED function as an intermediary. It felt kind of clever to write, but I don't believe in its fundamental usefulness.
CREATE OR REPLACE PACKAGE so18989249 IS
TYPE date_plsql_nested_table_type IS TABLE OF DATE;
dates date_plsql_nested_table_type;
FUNCTION dates_pipelined RETURN date_plsql_nested_table_type PIPELINED;
PROCEDURE use_plsql_nested_table_type;
END so18989249;
/
CREATE OR REPLACE PACKAGE BODY so18989249 IS
FUNCTION dates_pipelined RETURN date_plsql_nested_table_type
PIPELINED IS
BEGIN
IF (dates.count > 0)
THEN
FOR i IN dates.first .. dates.last
LOOP
IF (dates.exists(i))
THEN
PIPE ROW(dates(i));
END IF;
END LOOP;
END IF;
END;
PROCEDURE use_plsql_nested_table_type IS
BEGIN
dates := NEW date_plsql_nested_table_type();
-- tweak these values as you see fit to produce the dbms_output results you want
dates.extend(5);
dates(1) := DATE '2013-12-25';
dates(2) := DATE '2013-01-01';
dates(3) := DATE '2013-07-01';
dates(4) := DATE '2013-09-03';
dates(5) := DATE '2008-11-18';
FOR i IN (SELECT o.owner,
o.object_name,
o.object_type,
to_char(o.last_ddl_time, 'YYYY-MM-DD') AS last_ddl
FROM all_objects o
WHERE trunc(o.last_ddl_time) IN
(SELECT column_value FROM TABLE(dates_pipelined))
--uses pipeline function which uses pl/sql-defined nested table
)
LOOP
dbms_output.put_line('"' || i.owner || '"."' || i.object_name || '" ("' || i.object_type || ') on ' || i.last_ddl);
END LOOP;
END;
END so18989249;
/
begin so18989249.use_plsql_nested_table_type; end;
/
The type has to be created at SQL level, not in a package. An SQL query doesn't know how to use any types defined in PL/SQL. So you'd have to do:
CREATE OR REPLACE TYPE t_brth_dt IS TABLE OF date;
/
... and remove the type from your package specification. (Or give them different names, at least, and they won't be interchangeable in use). Because it's at SQL level, you also can't use sourceTable.stdt_brth_dt%TYPE in the declaration, unfortunately.