I found this PL/SQL at my workplace and I couldn't find the reason why this script takes so much time to execute:
DECLARE
query VARCHAR(500);
ref_cur REFCURSOR;
product_listH VARCHAR(1000):='';
product_listA VARCHAR(1000):='';
product_listP VARCHAR(1000):='';
product VARCHAR(100):='';
begin
query := ' select hotelname
from sch1.resconfirmsv rr,
sch1.reshoteldetailssv hd,sch2.respkgconfirmsv r '||
' where rr.id = hd.resconfirmid and
hd.resconfirmid = r.hotelconfirmid and
r.id = ' || m_resconfirmid || '';
OPEN ref_cur FOR EXECUTE query;
LOOP
FETCH ref_cur INTO product;
IF NOT FOUND THEN
EXIT; -- exit loop
END IF;
product_listH := product_listH||''||trim(COALESCE(product,'-'))||',<br>';
END LOOP;
product_listH := rtrim(trim(product_listH),',<br>');
CLOSE ref_cur;
query := ' select distinct programname
from sch1.resconfirmsv rr,
sch3.resactivitysv a,
sch3.resprogramsv hx,
sch2.respkgconfirmsv r '||
' where rr.id = hx.resconfirmid and
hx.id=a.resprogramid and
hx.resconfirmid = r.activitiesconfirmid and
r.id = ' || m_resconfirmid || '';
OPEN ref_cur FOR EXECUTE query;
LOOP
FETCH ref_cur INTO product;
IF NOT FOUND THEN
EXIT; -- exit loop
END IF;
product_listA := product_listA||''||trim(COALESCE(product,'-'))||',<br>';
END LOOP;
product_listA := rtrim(trim(product_listA),',<br>');
CLOSE ref_cur;
product_listP := product_listH || ',<br>' || product_listA;
product_listP := rtrim(trim(product_listP),',<br>');
product_listP = ltrim(rtrim(product_listP,',<br>'),',<br>');
RETURN product_listP;
end;
without this script total run-time is 12.176 sec and with this script it takes up to 18.802 sec.means this gets at least 6 seconds to execute. All the needed columns are indexed. Anybody can tell me where the places need to be more optimize in this query?
Why declaring the cursor as a seperate varchar?
Instead i'd use the normal declaration of a cursor, it takes time to analyze the query to be executed by Oracle, so (between the declare- and Begin-labels of your current code:
cursor ref_cur as
select distinct programname
from sch1.resconfirmsv rr,
sch3.resactivitysv a,
sch3.resprogramsv hx,
sch2.respkgconfirmsv r '||
where rr.id = hx.resconfirmid and
hx.id=a.resprogramid and
hx.resconfirmid = r.activitiesconfirmid and
r.id = m_resconfirmid;
Now you can use
For x in ref_cur loop
The same thing for query#2.
Cheers
Related
I have three tables, viz:
Mains_Control
Control_Mapping
Control_Details
along with several conditions and columns. But I am performing dynamic operations on the tables columns given below.
I am unable to write a dynamic SQL block in PL-SQL procedure for the below conditions. Could anyone please assist me on this particular scenario.
SELECT *
FROM CUR_ALL_CONTENTS
WHERE MAINS_CONTROL SWITCH = $SWITCH
AND ($ATTRIB_COLUMNS = $ATTRIB_VAL
OR $ATTRIB_COLUMNS = $ATTRIB_VAL)
The above business condition is this
SELECT *
FROM CUR_ALL_CONTENTS
WHERE MAINS_CONTROL_SWITCH = 'TYPE'
AND (SWITCH_MODE = 'THRUST' OR SWITCH_MODE_GEAR = 'SEC_GEAR')
Here SWITCH attribute value can change, ATTRIB_COLUMNS and ATTRIB_VAL can change.
Mains_Control table has the following columns
SWITCH ACTION_CODE RULE_MAP_1
TYPE ON R1
TYPE OFF R2
METHOD HOLD R3
METHOD TERM_IN R4
Control_Mapping table has the following columns
RULE_MAP_1 RULE_MAP_2
R1 M11
R2 M22
R3 M33
R4 M44
Control_Details table has the following columns
RULE_MAP_2 ATTRIB_COLUMNS OPERAND ATTRIB_VAL
M11 SWTICH_MODE = THRUST
M22 SWITCH_MODE_GEAR = SEC_GEAR
M33 HOLD_RELEASE <> END
Still not clear for me how you determine which condition shall be used and when. Let's give this example with hard-coded rule set:
DECLARE
sqlstr VARCHAR2(30000);
cur INTEGER;
res INTEGER;
refCur SYS_REFCURSOR;
val Mains_Control.SWITCH%TYPE;
CURSOR Conditions IS
SELECT *
FROM RULE_MAP_2 IN ('M11', 'M22');
BEGIN
cur := DBMS_SQL.OPEN_CURSOR;
sqlstr := 'SELECT * '||CHR(13);
sqlstr := sqlstr || 'FROM CUR_ALL_CONTENTS '||CHR(13);
sqlstr := sqlstr || 'WHERE MAINS_CONTROL_SWITCH = :switch AND (';
FOR aCond IN Conditions LOOP
sqlstr := sqlstr || aCond.ATTRIB_COLUMNS ||aCond.OPERAND||' :'||RULE_MAP_2 ||' OR '
END LOOP;
sqlstr := REGEXP_REPLACE(sqlstr, ' OR ', ')');
DBMS_OUTPUT.PUT_LINE(sqlStr); --> verify generated statement
DBMS_SQL.PARSE(cur, sqlStr, DBMS_SQL.NATIVE);
SELECT SWITCH
INTO val
FROM Mains_Control
WHERE RULE_MAP_1 = 'R1';
DBMS_SQL.BIND_VARIABLE(cur, ':switch', sw);
FOR aCond IN Conditions LOOP
DBMS_SQL.BIND_VARIABLE(cur, ':'||aCond.RULE_MAP_2, aCond.ATTRIB_VAL);
END LOOP;
res := DBMS_SQL.EXECUTE(cur);
refCur := DBMS_SQL.TO_REFCURSOR(cur);
FETCH refCur BULK COLLECT INTO ...;
END;
The code would be simpler without DBMS_SQL.BIND_VARIABLE, however using bind variables is the proper way of doing it.
create or replace function lstnation (listdisplay in varchar2)
return varchar2 is
nName varchar2 (1000) default null;
listD varchar2(1000) default null;
cursor display_nation
is
select nation.n_name
from nation
inner join region
on region.r_regionkey = nation.n_nationkey
where region.r_regionname = listdisplay;
BEGIN
open display_nation;
loop
fetch display_nation into nName;
exit when display_nation%notfound;
IF
listD := listD || RTRIM(nName)||' , ';
end loop;
close display_nation;
return listD;
end lstnation;
/
DECLARE
rKey region.r_regionkey%type;
rName region.r_name%type;
nList varchar2(1000);
cursor outer_block is
select region.r_regionkey, region.r_name, lstnation(region.r_name)
from region;
BEGIN
open outer_block;
loop
fetch outer_block into rKey, rName, nList;
exit when outer_block%notfound;
dbms.output.put_line(rkey || ' ' || RTRIM(rName) || ': '|| nList);
end loop;
close outer_block;
end;
/
I get two errors, how can I fix it
LINE/COL ERROR
19/12 PLS-00103: Encountered the symbol "=" when expecting one of the
following:
. ( * # % & = - + < / > at in is mod remainder not rem then
<an exponent (**)> <> or != or ~= >= <= <> and or like like2
like4 likec between || multiset member submultiset
20/2 PLS-00103: Encountered the symbol "END" when expecting one of the
following:
begin function pragma procedure subtype type
current cursor delete
exists prior
You can save some coding and efficiency by replacing the cursor loop with the listagg function
select listagg(rtrim(nation.n_name),',')
from nation
inner join region
on region.r_regionkey = nation.n_nationkey
where region.r_regionname = listdisplay;
So that will collate all the matching rows, and use whatever delimiter is passed in. One thing to be aware of, you have listD varchar2(1000) so as long as the results from the query are less than 1000, you are OK. If you expect a larger result set, you may need to increase or use a clob.
If for some reason, you still want to use the loop method, then you need to fix your IF statement:
loop
fetch display_nation into nName;
exit when display_nation%notfound;
IF <condition> THEN
listD := listD || RTRIM(nName)||' , ';
END IF;
end loop;
I created the following PL/SQL anonymous block. The cursor below retrieves data from the select statement:
select mod_benutzer, count(*)
from dok_auspraegung
where parent_objekt_id = 1093
group by mod_benutzer;
This statement displays exactly two records:
DDMS_USER | 8
HU2MAMU | 14
But when I want to display these two records by cursor, it displays "HU2MAMU|14" two times like below:
Modifications:
DDMS_USER, 8x
HU2MAMU, 14x
HU2MAMU, 14x
declare
my_exception_1 exception;
var_parent_objekt_id dok_auspraegung.parent_objekt_id%TYPE := 1093;
var_date varchar(30);
var_mod_benutzer varchar2(10);
var_benutzer_modifs number;
cursor cursor_dok_auspraegung
is select mod_benutzer, count(*) from dok_auspraegung
where parent_objekt_id = 10935797565
group by mod_benutzer;
begin
select distinct to_char(mod_datum,'YYYY-MON-DD') into var_date from dok_auspraegung where parent_objekt_id = var_parent_objekt_id;
IF var_date is not null THEN
dbms_output.put_line('Parent Object ID' || ': ' || var_parent_objekt_id);
dbms_output.put_line('Date: ' || ' ' || var_date);
ELSE RAISE my_exception_1;
END IF;
open cursor_dok_auspraegung;
dbms_output.put_line('Modifications:');
loop
fetch cursor_dok_auspraegung into var_mod_benutzer, var_benutzer_modifs;
dbms_output.put(var_mod_benutzer);
dbms_output.put_line(', ' || var_benutzer_modifs || 'x');
exit when cursor_dok_auspraegung%notfound;
end loop;
dbms_output.put_line(cursor_dok_auspraegung%rowcount);
close cursor_dok_auspraegung;
exception
when NO_DATA_FOUND then
dbms_output.put_line('Parent Object ID not found!');
when my_exception_1 then
dbms_output.put_line('');
end;
What is the reason of that?
Because exiting from the cursor occurs after printing the value of the variables in the current case, this repeats the last value to be printed. So, it should occur before printing as follows
loop
fetch cursor_dok_auspraegung into var_mod_benutzer, var_benutzer_modifs;
exit when cursor_dok_auspraegung%notfound;
dbms_output.put(var_mod_benutzer);
dbms_output.put_line(', ' || var_benutzer_modifs || 'x');
end loop;
For example i have an array like
"a(1):=1 ,a(2):=2, a(3) := 3"
and now my array count =3 "(a.count)"
then i delete middle member "a.delete(2)" then i wanna make my array like this "a(1):=1;a(2):=3" and my array count = 2 ("a.count") how can i do this ?
ps:i need to this with big sized array so i think i should use, for or while loop but how...
The collection where you have deleted some element is called sparse collection. Below you have example how to iterate that type of collection and how to use it with forall.
declare
type a is table of number;
ar a;
v_idx number;
begin
select level bulk collect into ar from dual connect by level< 1000;
ar.delete(1);
ar.delete(4);
ar.delete(10);
ar.delete(88);
v_idx := ar.first;
while v_idx is not null loop
dbms_output.put_line('idx: '||v_idx ||' value:'|| ar(v_idx));
v_idx := ar.next(v_idx);
end loop;
-- FORALL i IN INDICES OF ar
-- INSERT INTO test_table VALUES ar(i);
end;
Thank you but i should change array too , i need to take same output when i print array members like
for i in ar.first..ar.last loop
dbms_output.put_line(ar(i));
end loop;
declare
type a is table of number;
ar a;
begin
select level bulk collect into ar from dual connect by level< 1000;
ar.delete(1);
ar.delete(4);
ar.delete(10);
ar.delete(88);
-- ar is sparse collection;
ar := ar MULTISET intersect ar;
-- ar is dense collection and for i in .... is possible
FOR i IN ar.first .. ar.last LOOP
DBMS_OUTPUT.put_line(ar(i));
END LOOP;
end;
you can try this approach assign values of first spared collection to second continues collection and use second collection for further processing...
declare
type num_arr is table of number;
v_num_arr1 num_arr; --first collection
v_num_arr2 num_arr := num_arr(); -- second collection initialization and declaration
v_idx number;
v_col_index number := 1;
begin
-- fill 10 element.
select level || '1' as num1 bulk collect into v_num_arr1 from dual connect by level < 10;
for x in v_num_arr1.first .. v_num_arr1.last loop
dbms_output.put_line('index: ' || x || ' value: ' || v_num_arr1(x));
end loop;
dbms_output.put_line('');
-- delete element
v_num_arr1.delete(3);
v_num_arr1.delete(7);
v_idx := v_num_arr1.first;
while v_idx is not null loop
dbms_output.put_line('index: ' || v_idx || ' value: ' || v_num_arr1(v_idx));
-- filling second collection with regular index by variable v_col_index
if v_num_arr1(v_idx) is not null then
v_num_arr2.extend(1);
v_num_arr2(v_col_index) := v_num_arr1(v_idx);
v_col_index := v_col_index + 1;
end if;
v_idx := v_num_arr1.next(v_idx);
end loop;
dbms_output.put_line('second collection elements
');
--check second colleciton
for x in v_num_arr2.first .. v_num_arr2.last loop
dbms_output.put_line('index: ' || x || ' value: ' || v_num_arr2(x));
end loop;
end;
I have a program to generate dynamic query string based on input. This query may select from any tables or joined tables in my DB, and the column names and number of columns are unknown.
Now with this query string as the only input, I want to fetch all data from the result and output them line by line, is there any way to do this ?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Thank Thinkjet for the reference. I have solved the problem, to help the others, here is the piece of code I used:
DECLARE
v_curid NUMBER;
v_desctab DBMS_SQL.DESC_TAB;
v_colcnt NUMBER;
v_name_var VARCHAR2(10000);
v_num_var NUMBER;
v_date_var DATE;
v_row_num NUMBER;
p_sql_stmt VARCHAR2(1000);
BEGIN
v_curid := DBMS_SQL.OPEN_CURSOR;
p_sql_stmt :='SELECT * FROM emp';
DBMS_SQL.PARSE(v_curid, p_sql_stmt, DBMS_SQL.NATIVE);
DBMS_SQL.DESCRIBE_COLUMNS(v_curid, v_colcnt, v_desctab);
-- Define columns:
FOR i IN 1 .. v_colcnt LOOP
IF v_desctab(i).col_type = 2 THEN
DBMS_SQL.DEFINE_COLUMN(v_curid, i, v_num_var);
ELSIF v_desctab(i).col_type = 12 THEN
DBMS_SQL.DEFINE_COLUMN(v_curid, i, v_date_var);
ELSE
DBMS_SQL.DEFINE_COLUMN(v_curid, i, v_name_var, 50);
END IF;
END LOOP;
v_row_num := dbms_sql.execute(v_curid);
-- Fetch rows with DBMS_SQL package:
WHILE DBMS_SQL.FETCH_ROWS(v_curid) > 0 LOOP
FOR i IN 1 .. v_colcnt LOOP
IF (v_desctab(i).col_type = 1) THEN
DBMS_SQL.COLUMN_VALUE(v_curid, i, v_name_var);
ELSIF (v_desctab(i).col_type = 2) THEN
DBMS_SQL.COLUMN_VALUE(v_curid, i, v_num_var);
ELSIF (v_desctab(i).col_type = 12) THEN
DBMS_SQL.COLUMN_VALUE(v_curid, i, v_date_var);
END IF;
END LOOP;
END LOOP;
DBMS_SQL.CLOSE_CURSOR(v_curid);
END;
/
You can do that with DBMS_SQL package.
Update
To get more detailed reference about DBMS_SQL go here.
If you are building your string within PL/SQL, you can run it with EXECUTE IMMEDIATE. <- link. Use the BULK COLLECT INTO and output the collection.
<PRE>
DECLARE
RUN_S CLOB;
IGNORE NUMBER;
SOURCE_CURSOR NUMBER;
PWFIELD_COUNT NUMBER DEFAULT 0;
L_DESCTBL DBMS_SQL.DESC_TAB2;
Z_NUMBER NUMBER;
BEGIN
RUN_S := ' SELECT 1 AS VAL1,
2 AS VAL2,
CURSOR (SELECT 11 AS VAL11,
12 AS VAL12
FROM DUAL) AS CUR1,
CURSOR (SELECT 11 AS VAL11,
12 AS VAL12
FROM DUAL) AS CUR2
FROM DUAL';
SOURCE_CURSOR := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(SOURCE_CURSOR, RUN_S, DBMS_SQL.NATIVE);
DBMS_SQL.DESCRIBE_COLUMNS2(SOURCE_CURSOR, PWFIELD_COUNT, L_DESCTBL); -- get record structure
FOR I IN 1 .. PWFIELD_COUNT LOOP
DBMS_OUTPUT.PUT_LINE('Col ' || I || ' Type:' || L_DESCTBL(I).COL_TYPE);
IF L_DESCTBL(I).COL_TYPE = 2 THEN
DBMS_SQL.DEFINE_COLUMN(SOURCE_CURSOR, I, Z_NUMBER);
END IF;
NULL;
END LOOP;
IGNORE := DBMS_SQL.EXECUTE(SOURCE_CURSOR);
LOOP
IF DBMS_SQL.FETCH_ROWS(SOURCE_CURSOR) > 0 THEN
FOR I IN 1 .. PWFIELD_COUNT LOOP
IF L_DESCTBL(I).COL_TYPE IN (2) THEN
DBMS_SQL.COLUMN_VALUE(SOURCE_CURSOR, I, Z_NUMBER);
DBMS_OUTPUT.PUT_LINE('Col ' || I || ' Value:' || Z_NUMBER);
END IF;
END LOOP;
ELSE
EXIT;
END IF;
END LOOP;
END;
</PRE>