oracle, adding a new line to a nested table - oracle

I have these three object
create or replace
type type_client
( num int ,
username varchar(30),
balance int,
ta table_achat,
ref_admin ref type_admin,
member function get_prix_achat_total return int );
create or replace
type table_achat as table of achat ;
create or replace
type achat as object ( num_item int , qte int
);
create table table_client OF type_client ;
suppose in an entry of table_client .. we have a nested table like this :
(num_item,qte) : (1 , 5),(2 , 3)
what I want is the nested table be like this (for example):
(num_item,qte) : (1 , 5),(2 , 3)(3 , 44)
What I mean is, how to add a new line to an already created nested table while keeping existing entries? ..

We can use the MULTISET UNION operator to create a new set from two sets. In your case one of those sets is your existing set and the second set is the set of new entries.
Here is a demo based on a simplified version of your set-up:
declare
nt table_achat;
begin
nt := table_achat(achat(1 , 5),achat(2 , 3));
dbms_output.put_line(nt.count());
nt := nt multiset union table_achat(achat(3 , 44));
dbms_output.put_line(nt.count());
end;
/
Given a table T42 with a column COL_NT which is a nested table of your table_achat type you could insert a new entry in the nested table like this:
insert into the
(select col_nt from t42 where id = 1)
values (achat(3,44));

irrelevant from the question, which i couldn't and didn't try to understand, you can not combine insert + select + values statements as you did before. Perhaps you may prefer among below ones :
insert into the -- if table has one string column
(select ta from table_client where username=user);
OR
insert into the -- if table has two numeric columns
values (3,44);

Related

Can a type table of table%rowtype be indexed by some field of table%rowtype?

Why to I asked this question?
I have a table which as key that have a lot of field. Every time, I'm making a jointure, I miss a field. Therefore I have defined a pipelined function that take the key as an argument so that I am sure that I get only one element when I'm doing a jointure.
But the query take more time now. The table a has an index on some fields but not the table type used by pipelined function. I would like to know if it is possible to created a index on some fields of the table%rowtype
code:
create table a ( a1 integer);
create package p_a
as
type t_a iS TABLE of a%ROWTYPE;
function f(i_a1 integer) return t_a pipelined;
end;
CREATE PACKAGE BODY p_a
AS
CURSOR c_A (i_a1 INTEGER)
RETURN a%ROWTYPE
IS
SELECT t.*
FROM a t
WHERE t.a1 = i_a1;
FUNCTION f (i_a1 INTEGER)
RETURN t_a
PIPELINED
IS
BEGIN
FOR c IN c_a (i_a1)
LOOP
PIPE ROW (c);
END LOOP;
END;
END;
with b as( select 1 b1 from dual) select * from b cross apply (table(p_a.f(b.b1)));
the question
I've tried to index the type table by a field of a table like this
create table a ( a1 integer);
create package p_a2
as
type t_a iS TABLE of a%ROWTYPE index by a.a1%type;
function f(i_a1 integer) return t_a pipelined;
end;
PLS-00315: Implementation restriction: unsupported table index type
Is what I want to do possible. If not how to solve the performance problems mentioned in the introduction?
code
A TYPE is NOT a table and cannot be indexed.
When you do:
create package p_a
as
type t_a iS TABLE of a%ROWTYPE;
end;
/
You are defining a type and the type is a collection data type; an instance of that type is NOT a physical table and but is more like an in-memory array.
When you create a PIPELINED function:
function f(i_a1 integer) return t_a pipelined;
It does NOT return a table; it returns the collection data type.
When you do:
type t_a iS TABLE of a%ROWTYPE index by a.a1%type;
You are NOT creating an index on a table; you are changing to a different collection data type that is an associative array (like a JavaScript object or a Python dictionary) that stores key-value pairs.
An associative array is a PL/SQL data type and (with limited exceptions in later versions for insert, update and delete statements) cannot be used in SQL statements.
When you do:
SELECT * FROM TABLE(SYS.ODCIVARCHAR2LIST('a', 'b', 'c'));
or:
SELECT * FROM TABLE(p_a.f(1));
Then you are passing a collection data type to an SQL statement and the table collection expression TABLE() is treating the collection expression as if it was a table. It is still NOT a table.
If you want to use an index on the table then use the table (without a cursor or a pipeline function):
WITH b (b1) AS (
SELECT 1 FROM DUAL
)
SELECT *
FROM b
CROSS APPLY (
SELECT a.*
FROM a
WHERE a.a1 = b.b1;
);
I think the first line of your question says it all: "key that have a lot of field". If I understand correctly, the table has a primary key that consists of a large number of columns and because of that writing queries becomes a challenge.
It sounds like you're trying to do something pretty complex that should not be an issue at all.
Take a step back and ask yourself - does this need to be the primary key of the table ? Or can you use a surrogate key (identity column, sequence), use that as the primary key and just create a unique index on the set of field that currently make up the primary key. It will (1) simplify your data model and (2) make writing the queries a lot easier.

Compare differences before insert into oracle table

Could you please tell me how to compare differences between table and my select query and insert those results in separate table? My plan is to create one base table (name RESULT) by using select statement and populate it with current result set. Then next day I would like to create procedure which will going to compare same select with RESULT table, and insert differences into another table called DIFFERENCES.
Any ideas?
Thanks!
You can create the RESULT_TABLE using CTAS as follows:
CREATE TABLE RESULT_TABLE
AS SELECT ... -- YOUR QUERY
Then you can use the following procedure which calculates the difference between your query and data from RESULT_TABLE:
CREATE OR REPLACE PROCEDURE FIND_DIFF
AS
BEGIN
INSERT INTO DIFFERENCES
--data present in the query but not in RESULT_TABLE
(SELECT ... -- YOUR QUERY
MINUS
SELECT * FROM RESULT_TABLE)
UNION
--data present in the RESULT_TABLE but not in the query
(SELECT * FROM RESULT_TABLE
MINUS
SELECT ... );-- YOUR QUERY
END;
/
I have used the UNION and the difference between both of them in a different order using MINUS to insert the deleted data also in the DIFFERENCES table. If this is not the requirement then remove the query after/before the UNION according to your requirement.
-- Create a table with results from the query, and ID as primary key
create table result_t as
select id, col_1, col_2, col_3
from <some-query>;
-- Create a table with new rows, deleted rows or updated rows
create table differences_t as
select id
-- Old values
,b.col_1 as old_col_1
,b.col_2 as old_col_2
,b.col_3 as old_col_3
-- New values
,a.col_1 as new_col_1
,a.col_2 as new_col_2
,a.col_3 as new_col_3
-- Execute the query once again
from <some-query> a
-- Outer join to detect also detect new/deleted rows
full join result_t b using(id)
-- Null aware comparison
where decode(a.col_1, b.col_1, 1, 0) = 0
or decode(a.col_2, b.col_2, 1, 0) = 0
or decode(a.col_3, b.col_3, 1, 0) = 0;

Bulk ref cursor into nested table showing error

I Created a nested table
I Want to bulk ref cursor (C_get_cards) into the nested table created.
I Want to use nested table as one of the column in table STAT_QUERIES.
How do I combine all the three steps in a single procedure? Please correct me if my approach is wrong.
--Nested Table---
CREATE OR REPLACE TYPE T_card_details AS TABLE OF VARCHAR2(20) -- define type
/
CREATE TYPE Query AS OBJECT ( -- create object
CARD_QUERY T_card_details) -- declare nested table as attribute
/
CREATE TABLE STAT_QUERIES (
OBJECTTYPE VARCHAR2(50),
CATEGORY VARCHAR2(100),
CARD_QUERY T_card_details)
NESTED TABLE CARD_QUERY STORE AS CARD_QUERY_TAB;
select * FROM STAT_QUERIES
-- The cursor bulk collect into T_CARD details
CREATE OR REPLACE PROCEDURE NRMSP_INVENTORYSTATS IS
CURSOR C_get_cards
IS
SELECT
nt.name nt_name
,nd.name nd_name
,ct.name ct_name
,ps.name ps_name
,count(c.cardid)
FROM cardtype ct, card c, node n, nodetype nt, nodedef nd, provisionstatus ps
WHERE ct.name in ('SRA AMP', 'XLA AMP', 'SAM', 'ESAM')
AND ct.cardtypeid = c.card2cardtype
AND c.card2node = n.nodeid
AND n.node2nodetype = nt.nodetypeid
AND n.node2nodedef = nd.nodedefid
AND c.card2provisionstatus = ps.provisionstatusid
GROUP by nt.name, nd.name, ct.name, ps.name
;
TYPE cards_TAB_TYPE IS TABLE OF C_get_cards%ROWTYPE INDEX BY BINARY_INTEGER ;
T_card_details cards_TAB_TYPE ;
BEGIN
OPEN C_get_cards ;
FETCH C_get_cards
BULK COLLECT INTO T_card_details
LIMIT 250
;
END;
/
---INSERT INTO STAT_QUERIES---
INSERT INTO STAT_QUERIES
VALUES('CARD', 'Cards from Other Projects 2014', 'CARD_QUERY');

Cursor for loop using a selection instead of a table ( Oracle )

I'm writing a procedure to fill up a child table from a parent table. The child table however has more fields than the parent table ( as it should be ). I've conjured a cursor which point to a selection, which is essentially a join of multiple tables.
Here's the code I got so far :
CREATE OR REPLACE PROCEDURE Pop_occ_lezione
AS
x Lezione%rowtype;
CURSOR cc IS
WITH y as(
SELECT Codice_corso,
nome_modulo,
Data_inizio_ed_modulo diem,
Giorno_lezione,
ora_inizio_lezione o_i,
ora_fine_lezione o_f,
anno,
id_cdl,
nome_sede,
locazione_modulo loc
FROM lezione
join ( select id_cdl, anno, codice_corso from corso ) using (codice_corso)
join ( select codice_corso, locazione_modulo from modulo ) using (codice_corso)
join ( select nome_sede, id_cdl from cdl ) using (id_cdl)
WHERE
case
when extract (month from Data_inizio_ed_modulo) < 9 then extract (year from Data_inizio_ed_modulo) - 1
else extract (year from Data_inizio_ed_modulo)
end = extract (year from sysdate+365)
)
SELECT *
FROM y
WHERE sem_check(y.diem,sysdate+365) = 1;
--
BEGIN
FETCH cc into x;
EXIT when cc%NOTFOUND;
INSERT INTO Occr_lezione
VALUES (
x.Codice_corso,
x.Nome_modulo,
x.diem,x.giorno_lezione,
x.Ora_inizio_lezione,
to_date(to_char(next_day(sysdate,x.Giorno_lezione),'DD-MM-YYYY') || to_char(x.Ora_inizio_lezione,' hh24:mi'),'dd-mm-yyyy hh24:mi'),
to_date(to_char(next_day(sysdate,x.Giorno_lezione),'DD-MM-YYYY') || to_char(x.Ora_fine_lezione,' hh24:mi'),'dd-mm-yyyy hh24:mi'),
x.nome_sede,
0,
x.loc
);
END LOOP;
END;
/
But of course it won't work, because the variable x has the type of my initial table row, which has less columns then my selection. Unfortunately As far as I know a rowtype variable is needed to cycle trough a cursor, in order to fetch data from it. Can you see the contradiction? How can I change the code? Is there a certain type of variable which can be crafted to reflect a row from my query result? Or maybe a way to cycle trough the data in the cursor without using a support variable? Or maybe something entirely different? Please let me know.
Ok, so as suggested I tried something like this:
INSERT INTO Occr_lezione(
Codice_corso,
Nome_modulo,
Data_inizio_ed_modulo,
Giorno_lezione,
Ora_inizio_lezione,
Ora_fine_lezione,
Anno,
Id_cdl,
Nome_sede,
Locazione_modulo
)
WITH y as(
SELECT Codice_corso,
Nome_modulo,
Data_inizio_ed_modulo,
Giorno_lezione,
Ora_inizio_lezione,
Ora_fine_lezione,
Anno,
Id_cdl,
Nome_sede,
Locazione_modulo
FROM Lezione
join ( select Id_cdl, Anno, Codice_corso from Corso ) using (codice_corso)
join ( select Codice_corso, Locazione_modulo from Modulo ) using (Codice_corso)
join ( select Nome_sede, Id_cdl from Cdl ) using (id_cdl)
WHERE
case
when extract (month from Data_inizio_ed_modulo) < 9 then extract (year from Data_inizio_ed_modulo) - 1
else extract (year from Data_inizio_ed_modulo)
end = extract (year from sysdate+365)
)
SELECT *
FROM y
WHERE sem_check(y.Data_inizio_ed_modulo,sysdate+365) = 1;
END;
/
But it says PL/SQL: ORA-00904: "LOCAZIONE_MODULO": invalid identifier
which isn't true, because the query return a table in which such column is present... am I missing something?
The code is compiled with no errors, it occurs when I try to fire the procedure.
In the table Occr_lezione as you can see:
CREATE TABLE Occr_lezione (
Codice_corso varchar2(20) NOT NULL,
Nome_modulo varchar2(50) NOT NULL,
Data_inizio_ed_modulo date NOT NULL,
Giorno_lezione number(1) NOT NULL,
Ora_inizio_lezione date NOT NULL,
Data_inizio_occr_lezione date,
Data_fine_occr_lezione date NOT NULL,
Nome_sede varchar2(30) NOT NULL,
Num_aula varchar2(3) NOT NULL,
Tipo_aula varchar2(20) NOT NULL,
--
CONSTRAINT fk_Occr_lezione_lezione FOREIGN KEY (Codice_corso,Nome_modulo,Data_inizio_ed_modulo,Giorno_lezione,Ora_inizio_lezione) REFERENCES Lezione(Codice_corso,Nome_modulo,Data_inizio_ed_modulo,Giorno_lezione,Ora_inizio_lezione) ON DELETE CASCADE,
CONSTRAINT fk_Occr_lezione_aula FOREIGN KEY (Nome_sede,Num_aula,Tipo_aula) REFERENCES Aula(Nome_sede,Num_aula,Tipo_aula) ON DELETE SET NULL,
CONSTRAINT pk_Occr_lezione PRIMARY KEY (Codice_corso,Nome_modulo,Data_inizio_ed_modulo,Giorno_lezione,Ora_inizio_lezione,Data_inizio_occr_lezione),
CHECK ( trunc(Data_inizio_occr_lezione) = trunc(Data_fine_occr_lezione) ), -- data inizio = data fine // prenotazione giornaliera
CHECK ( Data_inizio_occr_lezione < Data_fine_occr_lezione ) -- ora inizio < ora fine // coerenza temporale
there is not a column named Locazione_modulo, however the last column Tipo_aula as the same type and size of Locazione modulo :
CREATE TABLE Modulo (
Codice_corso varchar2(20) NOT NULL,
Nome_modulo varchar2(50),
Locazione_modulo varchar2(20) NOT NULL,
--
CONSTRAINT fk_Modulo_Corso FOREIGN KEY(Codice_corso) REFERENCES Corso(Codice_corso) ON DELETE CASCADE,
CONSTRAINT pk_Modulo PRIMARY KEY(Codice_corso,Nome_modulo),
CHECK (Locazione_modulo IN ('Aula','Laboratorio','Conferenze'))
);
So it should be irrelevant, right?
If you really want to use explicit cursors, you can declare x to be of type cc%rowtype
CREATE OR REPLACE PROCEDURE Pop_occ_lezione
AS
CURSOR cc IS ...
x cc%rowtype;
...
Unless you are using explicit cursors because you want to be able to explicitly fetch the data into local collections that you can leverage later on in your procedure, code using implicit cursors tends to be preferrable. That eliminates the need to FETCH and CLOSE the cursor or to write an EXIT condition and it implicitly does a bulk fetch to minimize context shifts.
BEGIN
FOR x IN cc
LOOP
INSERT INTO Occr_lezione ...
END LOOP;
END;
Of course, in either case, I would hope that you'd choose more meaningful names for your local variables-- x and cc don't tell you anything about what the variables are doing.
If all you are doing is taking data from one set of tables and inserting it into another table, it would be more efficient to write a single INSERT statement rather than coding a PL/SQL loop.
INSERT INTO Occr_lezione( <<column list>> )
SELECT <<column list>>
FROM <<tables you are joining together in the cursor definition>>
WHERE <<conditions from your cursor definition>>

Update or insert based on if employee exist in table

Do want to create Stored procc which updates or inserts into table based on the condition if current line does not exist in table?
This is what I have come up with so far:
PROCEDURE SP_UPDATE_EMPLOYEE
(
SSN VARCHAR2,
NAME VARCHAR2
)
AS
BEGIN
IF EXISTS(SELECT * FROM tblEMPLOYEE a where a.ssn = SSN)
--what ? just carry on to else
ELSE
INSERT INTO pb_mifid (ssn, NAME)
VALUES (SSN, NAME);
END;
Is this the way to achieve this?
This is quite a common pattern. Depending on what version of Oracle you are running, you could use the merge statement (I am not sure what version it appeared in).
create table test_merge (id integer, c2 varchar2(255));
create unique index test_merge_idx1 on test_merge(id);
merge into test_merge t
using (select 1 id, 'foobar' c2 from dual) s
on (t.id = s.id)
when matched then update set c2 = s.c2
when not matched then insert (id, c2)
values (s.id, s.c2);
Merge is intended to merge data from a source table, but you can fake it for individual rows by selecting the data from dual.
If you cannot use merge, then optimize for the most common case. Will the proc usually not find a record and need to insert it, or will it usually need to update an existing record?
If inserting will be most common, code such as the following is probably best:
begin
insert into t (columns)
values ()
exception
when dup_val_on_index then
update t set cols = values
end;
If update is the most common, then turn the procedure around:
begin
update t set cols = values;
if sql%rowcount = 0 then
-- nothing was updated, so the record doesn't exist, insert it.
insert into t (columns)
values ();
end if;
end;
You should not issue a select to check for the row and make the decision based on the result - that means you will always need to run two SQL statements, when you can get away with one most of the time (or always if you use merge). The less SQL statements you use, the better your code will perform.
BEGIN
INSERT INTO pb_mifid (ssn, NAME)
select SSN, NAME from dual
where not exists(SELECT * FROM tblEMPLOYEE a where a.ssn = SSN);
END;
UPDATE:
Attention, you should name your parameter p_ssn(distinguish to the column SSN ), and the query become:
INSERT INTO pb_mifid (ssn, NAME)
select P_SSN, NAME from dual
where not exists(SELECT * FROM tblEMPLOYEE a where a.ssn = P_SSN);
because this allways exists:
SELECT * FROM tblEMPLOYEE a where a.ssn = SSN

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