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'm trying to use the sum function with a package function but running into an "invalid identifier" bug. Here's some example code with the error causing function commented
create or replace type numType as object
(
myNum number
)
;
/
create or replace type numTypes is table of numType;
/
create or replace package testNumberPackage as
function ReturnNum(in_numType numType) return number;
end;
/
create or replace package body testNumberPackage as
function ReturnNum(in_numType numType) return number is
begin
return in_numType.myNum;
end;
end;
/
declare l_numTypes numTypes;
l_count number;
begin
l_numTypes := numTypes();
for i in 1 .. 100 loop
l_numTypes.extend(1);
l_numTypes(l_numTypes.last) := numType(i);
end loop;
select sum(n.myNum) into l_count from table(l_numTypes) n;
select sum(testNumberPackage.ReturnNum(n)) into l_count from table(l_numTypes) n; --causes the error
dbms_output.put_line(l_count);
end;
/
The exact error for this code is
ORA-06550: line 11, column 42
PL/SQL: ORA-00904: "N": invalid identifier
ORA-6550: line 11, column 3:
PL/SQL: SQL Statement ignored
Thanks for any help.
The first issue is that you can't pass a table into a parameter by using its alias. It doesn't even make sense to try doing that.
The next issue is how to get the column mynum that is returned from the table(l_numTypes) into the correct format to pass into testNumberPackage.ReturnNum, since it's of NUMBER datatype, and the function is expecting a numtype parameter.
To do that, you need to pass in an object with that column, like so: numtype(n.mynum).
The following works for me:
declare
l_numTypes numTypes;
l_count number;
begin
l_numTypes := numTypes();
for i in 1 .. 100 loop
l_numTypes.extend(1);
l_numTypes(l_numTypes.last) := numType(i);
end loop;
select sum(n.myNum) into l_count from table(l_numTypes) n;
select sum(testNumberPackage.ReturnNum(numtype(n.mynum))) into l_count from table(l_numTypes) n; --causes the error
dbms_output.put_line(l_count);
end;
/
5050
Clear as mud?
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.
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 :)
Is it possible to use COUNT in some way that will give me the number of tuples that are in a .sql file? I tried using it in a query with the file name like this:
SELECT COUNT(*) FROM #q65b;
It tells me that the table is invalid, which I understand because it isn't a table, q65b is a file with a query saved in it. I'm trying to compare the number of rows in q65b to a view that I have created. Is this possible or do I just have to run the query and check the number of rows at the bottom?
Thanks
You can do this in SQL*Plus. For example:
Create the text file, containing the query (note: no semicolon!):
select * from dual
Save it in a file, e.g. myqueryfile.txt, to the folder accessible from your SQL*Plus session.
You can now call this from within another SQL query - but make sure the # as at the start of a line, e.g.:
SQL> select * from (
2 #myqueryfile.txt
3 );
D
-
X
I don't personally use this feature much, however.
Here is one approach. It's a function which reads a file in a directory, wraps the contents in a select count(*) from ( .... ) construct and executes the resultant statement.
1 create or replace function get_cnt
2 ( p_file in varchar2 )
3 return number
4 as
5 n pls_integer;
6 stmt varchar2(32767);
7 f_line varchar2(255);
8 fh utl_file.file_type;
9 begin
10 stmt := 'select count(*) from (';
11 fh := utl_file.fopen('SQL_SCRIPTS', p_file, 'R');
12 loop
13 utl_file.get_line(fh, f_line );
14 if f_line is null then exit;
15 elsif f_line = '/' then exit;
16 else stmt := stmt ||chr(10)||f_line;
17 end if;
18 end loop;
19 stmt := stmt || ')';
20 execute immediate stmt into n;
21 return n;
22* end get_cnt;
SQL>
Here is the contents of a sql file:
select * from emp
/
~
~
~
"scripts/q_emp.sql" 3L, 21C
And here is how the script runs:
SQL> select get_cnt ('q_emp.sql') from dual
2 /
GET_CNT('Q_EMP.SQL')
--------------------
14
SQL>
So it works. Obviously what I have posted is just a proof of concept. You will need to include lots of error handling for the UTL_FILE aspects - it's a package which can throw lots of exceptions - and probably some safety checking of the script that gets passed.