Needed get renumbered result set, for example:
CREATE OR REPLACE TYPE nums_list IS TABLE OF NUMBER;
CREATE OR REPLACE FUNCTION generate_series(from_n INTEGER, to_n INTEGER, cycle_max INTEGER)
RETURN nums_list PIPELINED AS
cycle_iteration INTEGER := from_n;
BEGIN
FOR i IN from_n..to_n LOOP
PIPE ROW( cycle_iteration );
cycle_iteration := cycle_iteration + 1;
IF cycle_iteration > cycle_max THEN
cycle_iteration := from_n;
END IF;
END LOOP;
RETURN;
END;
SELECT * FROM TABLE(generate_series(1,10,3));
Question is: there is guarantee, that oracle always will return result in that order? :
1
2
3
1
2
3
1
2
3
1
or maybe sometimes result will unexpected ordered, like this:
1
1
1
1
2
2
....
?
Pipelining negates the need to build huge collections by piping rows
out of the function as they are created, saving memory and allowing
subsequent processing to start before all the rows are generated
pipelined-table-functions
This means, it will start processing the rows before get fetched completely and that's why you are seeing unpredictable order.
Related
so I am trying to write to an array in PL/SQL, and I always get the subscript outside of limit error. I've seen similar posts and implemented everything based on those answers, I can't seem to find what I'm doing wrong. The line giving the error is "arr_quartosLivres(counter) := q.id;" I've tried to extend the array and it still doesn't work, however, either way, the look only runs 21 times (because there are only 21 values in the table quarto) so it shouldn't even need to be extended. Any help would be highly appreciated! Thank you
SET SERVEROUTPUT ON;
DECLARE
p_idReserva reserva.id%type := 408;
v_dataEntradaReserva reserva.data_entrada%type;
counter integer := 0;
type arr_aux IS varray(21) of quarto.id%type;
arr_quartosLivres arr_aux := arr_aux();
BEGIN
SELECT data_entrada INTO v_dataEntradaReserva FROM reserva WHERE id = p_idreserva;
FOR q IN (SELECT * FROM quarto)
LOOP
BEGIN
IF isQuartoIndisponivel(q.id, v_dataEntradaReserva)
THEN DBMS_OUTPUT.PUT_LINE('nao disponivel' || counter);
arr_quartosLivres(counter) := q.id;
ELSE DBMS_OUTPUT.PUT_LINE('disponivel' || counter);
END IF;
counter := counter + 1;
END;
END LOOP;
END;
The index values for varray begin with 1. Your logic is trying to use index value 0. Thus index out of range. BTW extend does not apply to varray, when declared a varray has a fixed size. You have 3 solutions: initialize counter to 1 instead of 0, or move incrementing it prior to its use as an index. Since as it stands you increment every time through the loop, even when the IF condition returns false and you do not use the counter as an index, leaving a NULL value in the array.But you use counter for 2 different purposes: Counting rows processed and index into the array. Since the row value may not be put into the array then your 3rd option is to introduce another variable for the index. Further there is no need for the BEGIN ... End block in the loop.
declare
p_idreserva reserva.id%type := 408;
v_dataentradareserva reserva.data_entrada%type;
counter integer := 0;
type arr_aux is varray(21) of quarto.id%type;
arr_quartoslivres arr_aux := arr_aux();
varray_index integer := 1 ; -- index varaibal for varray.
begin
select data_entrada into v_dataentradareserva from reserva where id = p_idreserva;
for q in (select * from quarto)
loop
if isquartoindisponivel(q.id, v_dataentradareserva)
then
dbms_output.put_line('nao disponivel' || counter || ' at index ' || varray_index);
arr_quartoslivres(varray_index) := q.id;
varray_index := varray_index + 1;
else
dbms_output.put_line('disponivel' || counter);
end if;
counter := counter + 1;
end loop;
end;
I'm trying to create a procedure, that checks if two values are present in a table.
The logic is as follows: Create a function called get_authority. This function takes two parameters (found in the account_owner table): cust_id and acc_id, and returns 1 (one), if the customer has the right to make withdrawals from the account, or 0 (zero), if the customer doesn't have any authority to the account. I'm writing plsql and using oracle live sql. I can't figure out how to handle the scenario where a customer has two accounts!
account_owner is seen here:
create or replace function get_authority(
p_cust_id in account_owner.cust_id%type,
p_acc_id in account_owner.acc_id%type
)
return varchar2
as
v_return number(1);
v_acc_id account_owner.acc_id%type;
v_cust_id account_owner.cust_id%type;
begin
for v_ in (select account_owner.cust_id,
account_owner.acc_id
from account_owner
where p_cust_id = cust_id)
LOOP
if p_cust_id = v_cust_id and p_acc_id = v_acc_id then
v_return := v_return + 1;
else
v_return := v_return + 0;
end if;
return v_return;
END LOOP;
end;
/
When I check for the cust_id I get the return 0 - but it should be 1??
select get_authority('650707-1111',123) from dual;
return:
GET_AUTHORITY('650707-1111',123)
0
What do I do wrong?
You got 0? How come; should be NULL.
v_return number(1);
so it is initially NULL. Later on, you're adding "something" to it, but - adding anything to NULL will be NULL:
SQL> select 25 + null as result from dual;
RESULT
----------
SQL>
Therefore, set its default value to 0 (zero):
v_return number(1) := 0;
Also, you declared two additional variables:
v_acc_id account_owner.acc_id%type;
v_cust_id account_owner.cust_id%type;
Then you compare them to values passed as parameters; as they are NULL, ELSE is executed.
Furthermore, there's a loop, but you don't do anything with it. If you meant that this:
for v_ in (select account_owner.cust_id,
(rewritten as for v_ in (select cust_id) evaluates to v_cust_id - it does not. Cursor variables are referred to as v_.cust_id (note the dot in between).
Also, if there's only one row per p_cust_id and p_acc_id, why do you use cursor FOR loop at all? To avoid no_data_found or too_many_rows? I wouldn't do that; yes, it fixes such "errors", but is confusing. You'd rather properly handle exceptions.
Here's what you might have done:
Sample data:
SQL> select * From account_owner;
ACCOW_ID CUST_ID ACC_ID
---------- ----------- ----------
1 650707-1111 123
2 560126-1148 123
3 650707-1111 5899
Function; if there are more rows per parameters' combination, max function will make sure that too_many_rows is avoided (as it bothers you). You don't really care what it returns - important is that select returns anything to prove that authority exists for that account.
SQL> create or replace function get_authority
2 (p_cust_id in account_owner.cust_id%type,
3 p_acc_id in account_owner.acc_id%type
4 )
5 return number
6 is
7 l_accow_id account_owner.accow_id%type;
8 begin
9 select max(o.accow_id)
10 into l_accow_id
11 from account_owner o
12 where o.cust_id = p_cust_id
13 and o.acc_id = p_acc_id;
14
15 return case when l_accow_id is not null then 1
16 else 0
17 end;
18 end;
19 /
Function created.
Testing:
SQL> select get_authority('650707-1111', 123) res_1,
2 get_authority('650707-1111', 5899) res_2
3 from dual;
RES_1 RES_2
---------- ----------
1 1
SQL>
I've created a tabular form from a view - so only the checked items be added to a table. So far I can only insert all the records not individually selected rows.
This is the code I used:
DECLARE
v_insertcount NUMBER := 0;
BEGIN
FOR i IN 1 .. apex_application.g_f02.COUNT
LOOP
IF apex_application.g_f01 (i) IS NOT NULL THEN -- this is the checkbox
insert into my_table (pme_id, MYREF, STAC, START_DATE)
values ( SEQ_PME.NEXTVAL,
:P5_MYREF
apex_application.g_f02(i),
apex_application.g_f03(i)
)
v_insertcount := v_insertcount + 1;
END IF;
END LOOP;
END;
First you have to remember that only checked checkboxes are submitted. So you cannot test for NULL in order to identify unchecked boxes. That are simply not in the array.
So, as the checkbox array size is lower or equal to the other fields array size, you cannot use index to find corresponding values of the same row.
There are some clever tricks to overcome that limitations. However, for simple cases, a solution is simply to use a look-up function to map id to index.
FUNCTION array_search(value IN VARCHAR2, arr IN apex_application_global.vc_arr2)
RETURN PLS_INTEGER
IS
BEGIN
FOR i IN 1 .. arr.COUNT
LOOP
IF arr(i) = value THEN
RETURN i;
END IF;
END LOOP;
return 0;
END;
This is a linear search. So the performances are not very good. Anyway for form processing it is probably sufficient. Given that function, you can now write:
Region source
SELECT APEX_ITEM.CHECKBOX(1,pme_id) " ",
...
on-submit process
FOR i IN 1 .. apex_application.g_f01.COUNT -- your checkboxes
LOOP
-- identify the "row index"
idx := array_search(apex_application.g_f01(i), apex_application.g_f02);
-- ^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^
-- checkboxes array id array
-- assuming now idx > 0
-- (in production code, should check and log in case of `0`)
-- do whatever you want, using `idx` as index
insert into my_table
(pme_id,
MYREF,
STAC,
START_DATE
)
values (
SEQ_PME.NEXTVAL,
:P5_MYREF
apex_application.g_f02 (idx),
apex_application.g_f03 (idx)
);
END LOOP;
I have a table like this:
id parent_id name
1 1 Root
2 1 Car
3 1 Plane
4 2 BMW
5 4 CLK
How can I dynamically create popup menu with all subitems in Delphi?
This is how it should look like:
Assuming root element has NULL as Parent_ID you can issue the request
Select ID, Parent_ID, Name from all_my_menus
order by Parent_ID nulls first, ID
where Menu_ID = :MenuIDParameter
1 <NULL> Root
8 <NULL> another root
2 1 Car
4 1 Plane
3 2 BMW
5 4 CLK
You would also cache in-memory created menu items: var MI_by_id: TDictionary<integer, TMenuItem>;
The traversing through the results would look like
var MI: TMenuItem;
MI_by_id: TDictionary<integer, TMenuItem>;
begin
MI_by_id := TDictionary<integer, TMenuItem>.Create;
try
While not Query.EOF do begin
MI := TMenuItem.Create(Self);
MI.Caption := Query.Fields[2].AsString;
MI.Tag := Query.Fields[0].AsInteger; // ID, would be helpful for OnClick event
MI.OnClick := ...some click handler
if Query.Fields[1].IsNull {no parent}
then MainMenu.Items.Add(MI)
else MI_by_id.Items[Query.Fields[1].AsInteger].Add(MI);
MI_by_id.Add(MI.Tag, MI); //save shortcut to potential parent for future searching
Query.Next;
end;
finally
MI_by_id.Free;
end;
end;
Actually, since we made sort upon Parent_ID on the query, all the children for given parent make single continuous list, so could be better to remove populated parents from the dictionary after we populated last child (i.e. after parent_ID got new value) and caching previously found parent otherwise in another local variable (instead of making yet another search through the dictionary).
However reasonable size for human-targeted menu should be much less to worth this. But you have to understand this approach most probably scales as O(n*n) thus would start loose speed very fast as the table grows.
http://docwiki.embarcadero.com/Libraries/XE3/en/Vcl.Menus.TMenuItem.Add
http://docwiki.embarcadero.com/CodeExamples/XE2/en/Generics.Collections.TDictionary_(Delphi)
Note: this also requires that for every non-root element ID > ParentID (put CHECK CONSTRAINT on the table)
1 <NULL> Root
8 <NULL> another root
7 1 Plane
3 4 BMW
4 7 CLK
5 8 Car
This would lead to BMW tied to create before its parent CLK created.
Violation for that conditions can be overcome by few means:
recursive load: select <items> where Parent_id is null, then for each of the added menu items do select <items> where Parent_id = :current_memuitem_id and so on that. This is like VirtualTreeView would work
ask SQL server to sort and flatten the tree - this is usually called self-recursive SQL selection and is server-dependant.
introduce one more collection variable - menu items w/o parent. After each new item added to the menu this collection should be searched if there are pending children to extract from it and move into the newly created parent.
Too many solutions for such a simple problem. Too bad you got ordered ID's because without ordered ID's things would have been more fun. Here's my own solution. On an empty form drop a button, a TClientDataSet and a TPopupMenu. Make the form's PopupMenu = PopupMenu1 so you can see the result. Add this to Button1.OnClick:
Note: I'm intentionally using TClientDataSet and not a real Query. This question is not about the query and this solution works with whatever TDataSet descendant you throw at it. Just make sure the result set is ordered on id, or else you could see the child nodes before the parents. Also note, half the code is used to fill up the ClientDataSet with the sample data in the question!
procedure TForm16.Button1Click(Sender: TObject);
var Prev: TDictionary<Integer, TMenuItem>; // We will use this to keep track of previously generated nodes so we do not need to search for them
CurrentItem, ParentItem: TMenuItem;
begin
if not ClientDataSet1.Active then
begin
// Prepare the ClientDataSet1 structure
ClientDataSet1.FieldDefs.Add('id', ftInteger);
ClientDataSet1.FieldDefs.Add('parent_id', ftInteger);
ClientDataSet1.FieldDefs.Add('name', ftString, 100);
ClientDataSet1.CreateDataSet;
// Fill the dataset
ClientDataSet1.AppendRecord([1, 1, 'Root']);
ClientDataSet1.AppendRecord([2, 1, 'Car']);
ClientDataSet1.AppendRecord([3, 1, 'Plane']);
ClientDataSet1.AppendRecord([4, 2, 'BMW']);
ClientDataSet1.AppendRecord([5, 4, 'CLK']);
end;
// Clear the existing menu
PopupMenu1.Items.Clear;
// Prepare the loop
Prev := TDictionary<Integer, TMenuItem>.Create;
try
ClientDataSet1.First; // Not required for a true SQL Query, only required here for re-entry
while not ClientDataSet1.Eof do
begin
CurrentItem := TMenuItem.Create(Self);
CurrentItem.Caption := ClientDataSet1['name'];
if (not ClientDataSet1.FieldByName('parent_id').IsNull) and Prev.TryGetValue(ClientDataSet1['parent_id'], ParentItem) then
ParentItem.Add(CurrentItem)
else
PopupMenu1.Items.Add(CurrentItem);
// Put the current Item in the dictionary for future reference
Prev.Add(ClientDataSet1['id'], CurrentItem);
ClientDataSet1.Next;
end;
finally Prev.Free;
end;
end;
Try this
procedure TForm1.MyPopup(Sender: TObject);
begin
with Sender as TMenuItem do ShowMessage(Caption);
end;
procedure TForm1.Button1Click(Sender: TObject);
var
MyItem,MySubItem1: TMenuItem;
begin
Inc(Num);
MyItem:=TMenuItem.Create(Self);
MySubItem1:=TMenuItem.Create(Self);
MyItem.Caption:='Hello'+IntToStr(Num);
MySubItem1.Caption:='Good Bye'+IntToStr(Num);
MainMenu1.Items.Add(MyItem);
MainMenu1.Items[0].Insert(num-1,MySubItem1);
MyItem.OnClick:=MyPopUp;
MySubItem1.OnClick:=MyPopUp;
end;
Taken from http://www.greatis.com/delphicb/tips/lib/components-addmenuitem.html
This solution requires parent_id of root to be 0, tested with
Select 1 as ID, 0 as Parent_ID, 'Root' as Name
union
Select 2, 1, ' Car'
union
Select 3 , 1, 'Plane'
union
Select 4, 2, 'BMW'
union
Select 5, 4, 'CLK'
should by optimized, have just a lack of time ...
Function GetMenu(pop:TPopupmenu;ID:Integer):TMenuItem;
var
i:Integer;
Function CheckItem(mi:TMenuItem):TMenuItem;
var
i:Integer;
begin
Result := nil;
if mi.Name = 'DYN_' + INtToStr(ID) then Result := mi
else for i := 0 to mi.Count-1 do
if not Assigned(Result) then Result := CheckItem(mi[i]);
end;
begin
Result := nil;
for i := 0 to pop.Items.Count-1 do
begin
if not Assigned(Result) then Result := CheckItem(pop.Items[i]);
if Assigned(Result) then Break;
end;
end;
Function InsertMenuItem(pop:TPopupMenu;mi:TMenuItem;ID:Integer;Const caption:String):TMenuItem;
begin
Result := TMenuItem.Create(pop);
Result.Caption := caption;
Result.Name := 'DYN_' + INtToStr(ID) ;
if not Assigned(mi) then pop.Items.Add(Result) else mi.Add(Result);
end;
Function AddMenuItem(pop:TPopupmenu;ID:Integer;Ads:TDataset):TMenuItem;
begin
Ads.Locate('ID',ID,[]);
Result := GetMenu(pop,id);
if (not Assigned(Result)) then
begin
if (Ads.FieldByName('parent_ID').AsInteger<>0) then
begin
result := AddMenuItem(pop,Ads.FieldByName('parent_ID').AsInteger,Ads);
Ads.Locate('ID',ID,[]);
end;
Result := InsertMenuItem(pop,Result,ID,Ads.FieldByName('Name').AsString);
end;
Ads.Locate('ID',ID,[]);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
while not ADS.Eof do
begin
AddMenuItem(Popupmenu1,ads.FieldByName('ID').AsInteger,Ads);
Ads.Next
end;
end;
Interesting conundrum ...another late night thought, a practical answer for re-use :)
Make a derived component:
type
TCascadeMenuItem = class(TMenuItem)
private
Id: Integer;
public
function AddItem(const ToId, WithId: Integer; AName: string): Boolean;
end;
with code
function TCascadeMenuItem.AddItem(const ToId, WithId: Integer; AName: string): Boolean;
var
i: Integer;
cmi: TCascadeMenuItem;
begin
if ToId = Id then
begin
cmi := TCascadeMenuItem.Create(Owner);
cmi.Caption := AName;
cmi.Id := WithId;
Add(cmi);
Result := True;
end
else begin
i := 0;
Result := False;
while (i < Count) and (not Result) do
begin
Result := TCascadeMenuItem(Items[i]).AddItem(ToId,WithId, ANAme);
inc(i);
end;
end;
end;
Main form, Assumes your data:
procedure TForm4.Button2Click(Sender: TObject);
var
mi: TCascadeMenuItem;
i: Integer;
Added: Boolean;
begin
cds1.First;
while not cds1.Eof do
begin
i := 0;
Added := False;
while (i < pup.Items.Count) and (not Added) do
begin
Added := TCascadeMenuItem(pup.Items[i]).AddItem(cds1Parent_Id.AsInteger, cds1id.AsInteger, cds1name.AsString);
inc(i);
end;
if not Added then
begin // new root
mi := TCasCadeMenuItem.Create(Self);
mi.Caption := cds1name.AsString;
mi.id := cds1Parent_Id.AsInteger;
pup.Items.Add(mi);
end;
cds1.Next;
end;
end;
You could derive a TCascasePopupMenu and put it on the palette :)
I have field in a Oracle database of type CLOB. I would like to split this field in several columns and rows. Here's an example of the content:
4:true5:false24:<p>option sample 1.</p>4:true22:<p>option sample 2.</p>5:false23:<p>option sample 3.</p>5:false22:<p>option sample 4.</p>5:false
The result should look like this:
ID LEVEL ANSWER_OPTION VALUE
1 3 option sample 3 false
1 4 option sample 4 false
2 3 option sample 3 false
4 3 option sample 3 true
3 2 option sample 2 false
1 2 option sample 2 true
2 1 option sample 1 true
2 4 option sample 4 false
4 1 option sample 1 false
2 2 option sample 2 false
4 2 option sample 2 false
1 1 option sample 1 false
3 4 option sample 4 false
4 4 option sample 4 false
3 3 option sample 3 false
3 1 option sample 1 true
We have made the following statement which created the result above.
with guest_string as
( select qsn.id id
, dbms_lob.substr( qsn.guest, 2000, 1 ) answer_options
from mneme_question qsn
where qsn.id < 10
)
select distinct id
, level
, substr(regexp_substr( answer_options'<p>[^<]+', 1, level, 'i'), 4) ANSWER_OPTION
, substr(regexp_substr( answer_options, '(true|false)', regexp_instr( answer_options, '</p>', 1, 1), level, 'i'), 1) VALUE
from guest_string
connect by regexp_substr( answer_options, '<p>[^<]+', 1, level, 'i') is not null
The problem with this code is it takes way to long to split all records we have. We had to cut it off at 10 rows (5 row take 0.25 sec, 10 takes 16 seconds, 15 rows takes about over 2,5 minutes). We currently have 30000 rows and they will grow. At the moment we cannot change the software to change the datamodel, so we will have to do this ad hoc.
Our current approach is to create a procedure that will be called for each record, but it would be better to have a faster parsing. Does anybody have a suggestion how to create a script that can do this in a reasonable time. We can do this at night time, but preferably it shouldn't take longer than 2 minutes.
BTW in the future we could build some sort of mechanism to determine which records have already been parsed, but that also requires some form of detecting already parsed fields that have changed in the mean time. We don't have time to do that yet, so for now we need crude parsing as fast as possible.
Thanks
Here is a different approach.
The code may not be as nice as it can, and you will probably have to fix some small things...
I checked it on 11g (couldn't find 10g) and used your input as the values in my clob column.
For 10 rows (all with the same input as you gave as example),
original query: 9.8 sec
new query: 0.08 sec
I used a pipelined function, here is the code:
create or replace type t_parse is object(idd number, levell number, answer_option varchar2(128), valuee varchar2(4000));
/
create or replace type tab_parse is table of t_parse;
/
create or replace function split_answers return tab_parse
pipelined is
cursor c is
select * from mneme_question;
str_t clob;
phraseP varchar2(128);
phraseV varchar2(8);
i1s number;
i1e number;
i2s number;
levell number;
begin
for r in c loop
str_t := r.guest;
levell := 1;
while str_t is not null loop
i1s := dbms_lob.instr(str_t, '<p>', 1, 1) + 3;
if i1s = 3 then
str_t := '';
else
i1e := dbms_lob.instr(str_t, '</p>', 1, 1);
phraseP := dbms_lob.substr(str_t, i1e - i1s, i1s);
str_t := dbms_lob.substr(str_t, offset => i1e + 4);
i2s := dbms_lob.instr(str_t, 'true', 1, 1) ;
if i2s = 0 then
i2s := dbms_lob.instr(str_t, 'false', 1, 1) ;
if i2s = 0 then
str_t := '';
else
phraseV := dbms_lob.substr(str_t, 5, i2s);
pipe row(t_parse(r.id, levell, phraseP, phraseV));
levell := levell + 1;
end if;
else
phraseV := dbms_lob.substr(str_t, 4, i2s);
pipe row(t_parse(r.id, levell, phraseP, phraseV));
levell := levell + 1;
end if;
end if;
end loop;
end loop;
return;
end split_answers;
/
new query should be like:
select * from table(split_answers);
There is some function whis returning pipelined table:
CREATE OR REPLACE FUNCTION split_clob(p_clob IN CLOB DEFAULT NULL,
p_varchar IN VARCHAR2 DEFAULT NULL,
p_separator IN VARCHAR2)
RETURN varchar_set
PIPELINED IS
l_clob CLOB;
BEGIN
l_clob := nvl(p_clob,
to_clob(p_varchar));
FOR rec IN (
WITH vals AS
(SELECT CAST(TRIM(regexp_substr(l_clob,
'[^'||p_separator||']+',
1,
levels.column_value)) AS
VARCHAR2(320)) AS val
FROM TABLE(CAST(MULTISET
(SELECT LEVEL
FROM dual
CONNECT BY LEVEL <=
length(regexp_replace(l_clob,
'[^'||p_separator||']+')) + 1) AS
sys.odcinumberlist)) levels)
SELECT val FROM vals)
LOOP
PIPE ROW(rec.val);
END LOOP;
RETURN;
END;
U can use it like this:
-with table with clob
SELECT t2.column_value FROM my_table t, TABLE(split_clob(p_clob => t.clob_column,p_separator => ',')) t2
-or with varchar too
SELECT * FROM TABLE(split_clob(p_varchar => '1,2,3,4,5,6, 7, 8, 9', p_separator => ','))