Im new with SQL, and I want to knw how can I add a SQL in this structure to check if the row already exists before insert, Im tried this way, but I think its not the best.
DECLARE
v_project_id NUMBER;
v_group_name VARCHAR2(100);
v_user_id NUMBER;
v_group_id NUMBER;
BEGIN
FOR project IN (
SELECT project_id
FROM JSON_TABLE(:p_request,
'$' COLUMNS(NESTED PATH '$.projects[*]'
COLUMNS(
project_id VARCHAR2(100) PATH '$.project.id'
)
)
)
)
LOOP
v_project_id := project.project_id;
v_group_name := json_value (:p_request,'$.group_name');
v_user_id := json_value (:p_request,'$.user_id');
v_group_id := s_project_group.NEXTVAL;
dbms_output.put_line(v_group_id||' - '||v_group_name||' - '||v_user_id||' - '||v_project_id);
--------- HERE, I WANT TO CHECK IF THE NEW ROW ALREADY EXISTS BEFORE INSERT, IM TRIED THIS WAY, BUT I THINK ITS NOT THE BEST------------
(select case
when NOT exists (select 1 FROM APP_PROJECT_GROUP WHERE GROUP_NAME = :v_group_name AND USER_ID = :v_user_id)
INSERT INTO APP_PROJECT_GROUP (GROUP_ID, GROUP_NAME, PROJECT_ID, USER_ID) VALUES (v_group_id, v_group_name, v_project_id, v_user_i)
);
----------------------------------------------------------------------------------------------------------------------------------------
COMMIT;
END LOOP;
END;
As I commented on your previous question, use a MERGE statement then you can perform all the INSERTs in a single SQL statement (without having to use use cursor loops and repeatedly context-switching from PL/SQL to SQL):
MERGE INTO app_project_group dst
USING (
SELECT group_id,
group_name,
TO_NUMBER(project_id) AS project_id,
user_id
FROM JSON_TABLE(
:p_request,
'$'
COLUMNS(
group_name VARCHAR2(150) PATH '$.group_name',
group_id NUMBER(15) PATH '$.group_id',
user_id NUMBER(15) PATH '$.user_id',
NESTED PATH '$.projects[*]'
COLUMNS (
project_id VARCHAR2(15) PATH '$.project.id'
)
)
)
) src
ON (src.group_name = dst.group_name AND src.user_id = dst.user_id)
WHEN NOT MATCHED THEN
INSERT (group_id, group_name, project_id, user_id)
VALUES (s_project_group.NEXTVAL, src.group_name, src.project_id, src.user_id);
db<>fiddle here
Related
I have a table with these columns (id,first_name,birth). I want to create a procedure that insert a new customer only if the id inserted doesn't exist in the table. If it already exist, then don't insert it. This is my code so far, but I got an error 'line 3 sql statement ignored'. Any idea? I need to use procedure and pl sql in oracle. Thanks!
CREATE OR REPLACE PROCEDURE add_emp(v_id IN int,
v_name IN varchar2,
v_bday IN date) IS
BEGIN
INSERT INTO Employees
(Id, First_name, Birth)
SELECT *
FROM (SELECT v_id, v_name, v_bday) AS tmp
WHERE NOT EXISTS (SELECT Id FROM Employees WHERE Id = v_id);
END;
/
DECLARE
m_id int := 3;
m_name varchar2 := 'John';
m_bday date := '16-Dec-1990';
BEGIN
add_cust(m_id, m_name, m_bday);
END;
/
Your procedure has some syntax issue which is fixed in following code:
CREATE OR REPLACE PROCEDURE ADD_EMP (
V_ID IN INT,
V_NAME IN VARCHAR2,
V_BDAY IN DATE
) IS
BEGIN
INSERT INTO EMPLOYEES (
ID,
FIRST_NAME,
BIRTH
)
SELECT V_ID,
V_NAME,
V_BDAY
FROM DUAL -- FROM clause was missing
WHERE NOT EXISTS (
SELECT ID
FROM EMPLOYEES
WHERE ID = V_ID
);
END;
/
Also, Your calling PL/SQL block has some issues which are corrected in the following code:
DECLARE
M_ID INT := 3;
M_NAME VARCHAR2(10) := 'John'; -- varchar2 must be declared with size
M_BDAY DATE := DATE '1990-12-16'; -- added date literal to convert string to date
BEGIN
ADD_CUST(M_ID, M_NAME, M_BDAY);
END;
/
In Oracle SELECT does not work without a FROM clause (other DBMS products are different). So you need to provide a table; you can use DUAL, which is a dummy table provided by Oracle which is guaranteed to return one row.
INSERT INTO Employees(Id,First_name,Birth)
SELECT v_id, v_name, v_bday
from dual
WHERE NOT EXISTS (
SELECT Id FROM Employees WHERE Id = v_id
);
Your INSERT statement would work with a slight change
CREATE OR REPLACE PROCEDURE add_emp(v_id Employees.Id%type,
v_name Employees.First_name%type,
v_bday Employees.Birth%type) IS
BEGIN
INSERT INTO Employees
(Id, First_name, Birth)
SELECT v_id, v_name, v_bday
FROM dual
WHERE NOT EXISTS (SELECT * FROM Employees WHERE Id = v_id);
END;
/
You can replace INSERT statement with MERGE as an alternative DML such as
MERGE INTO Employees e1
USING
(SELECT v_id AS id, v_name AS First_name, v_bday AS birth
FROM dual) e2
ON ( e1.id = e2.id )
WHEN MATCHED THEN UPDATE SET e1.First_name = e2.First_name,
e1.Birth = e2.Birth -- If you need to change for the matching case
WHEN NOT MATCHED THEN INSERT( e1.id, e1.First_name, e1.birth )
VALUES( e2.id, e2.First_name, e2.birth );
I have 3 tables:
create table customer
(
customer_id integer primary key,
customer_first_name varchar2(50) not null,
customer_surrname varchar2(50) not null,
phone_number varchar2(15) not null,
customer_details varchar2(200) default 'There is no special notes'
);
create table place
(
table_number integer primary key,
table_details varchar2(200) default 'There is no details'
);
create table booking
(
booking_id integer primary key,
date_of_booking date,
number_of_persons number(2) not null,
customer_id integer not null,
foreign key(customer_id) references customer(customer_id),
table_number integer not null,
foreign key(table_number) references place(table_number)
);
I have to generate customer table using this kind of generator:
set SERVEROUTPUT on format wrapped;
set define off;
drop sequence customer_seq;
drop sequence place_seq;
--CUSTOMER TABLE INSERT ROW GENERATOR
create sequence customer_seq START WITH 1 INCREMENT BY 1 NOMAXVALUE;
CREATE OR REPLACE TRIGGER customer_id_trigger
BEFORE INSERT ON customer
FOR EACH ROW
BEGIN
SELECT customer_seq.nextval INTO :new.customer_id FROM dual;
END;
/
DELETE FROM customer;
DECLARE
TYPE TABSTR IS TABLE OF VARCHAR2(250);
first_name TABSTR;
surrname TABSTR;
qname number(5);
phonenum number(15);
details TABSTR;
BEGIN
first_name := TABSTR ('Jhon','Poul','Jesica','Arnold','Max','Teemo','Tim','Mikel','Michael',
'Kristian','Adela','Mari','Anastasia','Robert','Jim','Juana','Adward',
'Jana','Ola','Kristine','Natali','Corey','Chester','Naomi','Chin-Chou');
surrname := TABSTR ('Grey','Brown','Robins','Chiho','Lee','Das','Edwins','Porter','Potter',
'Dali','Jordan','Jordison','Fox','Washington','Bal','Pitney','Komarowski',
'Banks','Albra','Shwiger');
details := TABSTR ('Exellent Customer','Good Customer','Always drunked','Left big tips',
'Bad Customer','Did not pay last bill','New Customer','VIP client');
qname := 100; — CHANGE THIS TO MANAGE HOW MANY ROWS YOU WANT TO BE ADDED
FOR i IN 1..qname LOOP
phonenum := dbms_random.value(111111111,999999999);
INSERT INTO customer VALUES (NULL, first_name(dbms_random.value(1,25)),
surrname(dbms_random.value(1,20)), phonenum, details(dbms_random.value(1,8)));
END LOOP;
DBMS_OUTPUT.put_line('Customers done!');
END;
/
--TABLE INSERT
DELETE FROM place;
create sequence place_seq start with 1 increment by 1;
insert into place values (place_seq.nextval, 'Near the window');
insert into place values (place_seq.nextval, default);
insert into place values (place_seq.nextval, 'Near the door');
insert into place values (place_seq.nextval, 'Near the window');
insert into place values (place_seq.nextval, 'Near the window');
insert into place values (place_seq.nextval, default);
insert into place values (place_seq.nextval, 'Near the door');
insert into place values (place_seq.nextval, 'Big table');
insert into place values (place_seq.nextval, default);
insert into place values (place_seq.nextval, 'Big table');
So the question is how can I insert client_id in "booking" table which have one of the numbers in "customers" table? Because every time I regenerate data in "Customers" table numbers are changing so I should somehow select numbers in an array and then randomly choose one of them from this array. The thing is I don't really know how to select from table to array. Can anybody help?
For PL/SQL version you can use BULK COLLECT and standard sys.odcinumberlist array.
create sequence booking_seq start with 1 increment by 1;
declare
customerIds sys.odcinumberlist;
placeIds sys.odcinumberlist;
number_of_generated_records number := 150; -- number of records to be generated
begin
-- fill the array of customer_id values
select customer_id
bulk collect into customerIds
from customer;
-- fill the array of place numbers
select table_number
bulk collect into placeIds
from place;
for i in 1..number_of_generated_records loop
insert into booking(booking_id,date_of_booking,number_of_persons,customer_id,table_number)
values(
booking_seq.nextval, -- booking_id
trunc(sysdate) + round(dbms_random.value(1,365)), -- date_of_booking
round(dbms_random.value(1,99)), -- number_of_persons
customerIds(round(dbms_random.value(1,customerIds.count))), -- customer_id
placeIds(round(dbms_random.value(1,placeIds.count))) -- table_number
);
end loop;
end;
But, for your case I would prefer pure sql:
insert into booking(booking_id,date_of_booking,number_of_persons,customer_id,table_number)
with
customer_subq as (
select customer_id, row_number() over (order by customer_id) rn from customer
),
place_subq as (
select table_number, row_number() over (order by table_number) rn from place
),
params as (
select 1500 number_of_generated_records,
(select count(1) from customer) customer_count,
(select count(1) from place) place_count
from dual
),
random_numbers as (
select round(dbms_random.value(1,1000)) random_number1,
round(dbms_random.value(1,1000)) random_number2,
round(dbms_random.value(1,1000)) random_number3,
round(dbms_random.value(1,1000)) random_number4
from dual,params
connect by level <= number_of_generated_records
)
select booking_seq.nextval booking_id,
trunc(sysdate) + mod(random_number1,365) date_of_booking,
mod(random_number1,100) number_of_persons,
customer_id,
table_number
from random_numbers,
params,
customer_subq,
place_subq
where mod(random_number1,customer_count) + 1 = customer_subq.rn
and mod(random_number2,place_count) + 1 = place_subq.rn
I try to populate a table TBL in a loop. And get ORA-12704: character set mismatch on a subquery.
Here is a query I use:
BEGIN
FOR i IN (SELECT t.Stuff FROM STUFF_TABLE t ORDER BY t.Name ASC)
LOOP
INSERT INTO TBL(StuffId, StuffName)
VALUES(
i.Stuff,
(SELECT TempStuffName FROM
(SELECT COALESCE(st.StuffName, i.Stuff) as TempStuffName FROM STUFFDEFINITION st WHERE st.Stuff = i.Stuff ORDER BY st.Version DESC)
WHERE ROWNUM = 1)
);
END LOOP;
END;
The columns types are the following:
STUFF_TABLE.Stuff nvarchar2(30)
TBL.StuffId nvarchar2(30)
TBL.StuffName nvarchar2(50)
STUFFDEFINITION.Stuff varchar2(255)
STUFFDEFINITION.StuffName varchar2(255)
The issue, as I understand it, is in type casting namely from varchar2(255) to nvarchar2(50).
I tried to use CAST, Translate functions, but it didn't help. The ORA-12704: character set mismatch still occurs.
Is there a way to populate TBL in a loop as I try it to do?
Below is the test data to reproduce issue I talk about:
CREATE TABLE STUFF_TABLE
(
Stuff nvarchar2(30),
Name nvarchar2(50)
);
CREATE TABLE TBL
(
StuffId nvarchar2(30),
StuffName nvarchar2(50)
);
CREATE TABLE STUFFDEFINITION
(
Stuff varchar2(255),
StuffName varchar2(255),
Version number(19)
)
INSERT INTO STUFF_TABLE(Stuff, Name) VALUES('First', 'Name1');
INSERT INTO STUFF_TABLE(Stuff, Name) VALUES('Second', 'Name2');
INSERT INTO STUFF_TABLE(Stuff, Name) VALUES('Third', 'Name3');
INSERT INTO STUFFDEFINITION(Stuff, StuffName, Version) VALUES('First', 'First Stuff', 1);
INSERT INTO STUFFDEFINITION(Stuff, StuffName, Version) VALUES('First', 'First Stuff', 2);
INSERT INTO STUFFDEFINITION(Stuff, StuffName, Version) VALUES('Second', 'Second Stuff', 1);
INSERT INTO STUFFDEFINITION(Stuff, StuffName, Version) VALUES('Third', 'Third Stuff', 1);
From your statement its clear that you are joining a varchar2 column with nvarchar2 and inserting a varchar2 column to a nvarchar2 column. You need to do a conversion first. Try this:
BEGIN
FOR i IN (SELECT t.Stuff FROM STUFF_TABLE t ORDER BY t.Name ASC)
LOOP
INSERT INTO TBL(StuffId, StuffName)
VALUES(
i.Stuff,
(SELECT to_nchar(TempStuffName)
FROM
(SELECT COALESCE(to_nchar(st.StuffName), i.Stuff) as TempStuffName
FROM STUFFDEFINITION st
WHERE to_nchar(st.Stuff) = i.Stuff
ORDER BY st.Version DESC)
WHERE ROWNUM = 1)
);
END LOOP;
END;
You shouldn't need to use PL/SQL:
INSERT INTO TBL ( StuffId, StuffName )
SELECT TO_NCHAR( t.stuff ),
TO_NCHAR(
COALESCE(
MAX( d.StuffName ) KEEP ( DENSE_RANK LAST ORDER BY d.version ),
t.stuff
)
)
FROM StuffTable t
LEFT OUTER JOIN StuffDefinition d
ON ( t.stuff = TO_NCHAR( d.stuff ) )
GROUP BY t.stuff;
Oracle says this about that error: 'A string expression in the VALUES clause of an INSERT statement does not have the same character set as the column into which the value would be inserted.'
Please select from nls_database_parameters and tell me what the values of these are:
NLS_CHARACTERSET
NLS_NCHAR_CHARACTERSET
NLS_RDBMS_VERSION
NLS_LENGTH_SEMANTICS
I have two tables which are not fully equal but similar. They look like this:
CREATE TABLE FIRST_TABLE(
FIRST_ID RAW(16) NOT NULL CONSTRAINT FIRST_PK PRIMARY KEY,
FIRST_NAME VARCHAR2(2000),
FIRST_VALID NUMBER(1) NOT NULL,
AUDIT_CRE_AT TIMESTAMP(0) DEFAULT CURRENT_TIMESTAMP NOT NULL,
AUDIT_CRE_FROM VARCHAR2(32) DEFAULT 'system' NOT NULL,
CONSTRAINT SECOND_VALID CHECK (SECOND_VALID IN (0,1))
);
CREATE TABLE SECOND_TABLE(
SECOND_ID RAW(16) NOT NULL CONSTRAINT SECOND_PK PRIMARY KEY,
SECOND_NAME VARCHAR2(2000),
AUDIT_CRE_AT TIMESTAMP(0) DEFAULT CURRENT_TIMESTAMP NOT NULL,
AUDIT_CRE_FROM VARCHAR2(32) DEFAULT 'system' NOT NULL,
);
Now I want to migrate all records from the FIRST_TABLE into the SECOND_TABLE if the record is valid. A record is valid, if FIRST_VALID is 1.
That is what I want to to:
Select all valid records from FIRST_TABLE
SELECT * FROM FIRST_TABLE f WHERE f.FIRST_VALID like '1';
Loop through all records I got from the select query and INSERT everything except VALID INTO the SECOND_TABLE and DELETE them.
Thats where I got problems. This is what I have:
DECLARE
v_count_valids NUMBER(10):= 0;
v_i NUMBER(10):=0;
BEGIN
SELECT COUNT(*) INTO v_count_valids FROM FIRST_TABLE f WHERE f.VALID like '1';
WHILE v_i <= v_count_valids
LOOP
--INSERT INTO SECOND_TABLE VALUES (current record...)
--DELETE current record
v_i := v_i + 1;
END LOOP;
END;
Can you give me a hint how I can access the current in the loop record to insert some values into the other table? Or is there a better way to do this?
Just use insert . . . select:
insert into second_table(second_id, second_name, audit_cre_at, audit_cre_from)
SELECT first_id, first_name, audit_cre_at, audit_cre_from
FROM FIRST_TABLE f
WHERE f.FIRST_VALID = 1;
You don't need PL/SQL for this. Also, when comparing numbers, use numeric constants and =, not like and strings.
You don't need a loop. You could use an insert-select statement instead:
INSERT INTO second_table (second_id, second_name, audit_cre_at, audit_cre_from)
SELECT first_id, first_name, audit_cre_at, audit_cre_from
FROM first_table
WHERE valid = 1
As others mentioned, no need of writing PL/SQL code. First, put all your specific data from First_Table to Second_Table using below query.
INSERT INTO SECOND_TABLE(SECOND_ID, SECOND_NAME, AUDIT_CRE_AT, AUDIT_CRE_FROM)
SELECT FIRST_ID, FIRST_NAME, AUDIT_CRE_AT, AUDIT_CRE_FROM FROM FIRST_TABLE WHERE FIRST_VALID = 1;
And then, as you mentioned, you need to delete them. Then, write delete query
DELETE FROM FIRST_TABLE WHERE FIRST_VALID = 1;
I have made a procedure in PL/SQL which inserts data from one table to another on basis of primary key. My procedure is working fine but i can't figure out how will i update column CODE_NUMBER of my table MAIN if primary key already exists.
Actually i want rows of MAIN table to get UPDATED when its has primary key and insert data from REGIONS when primary key does not exists.
DECLARE
variable number;
id number;
description varchar2 (100);
CURSOR C1 IS
select regions.REGION_ID variable
from regions;
BEGIN
FOR R_C1 IN C1 LOOP
BEGIN
select regions.REGION_ID,regions.REGION_NAME
into id,description
from regions
where regions.REGION_ID = R_C1.variable;
----If exists then update otherwise insert
INSERT INTO MAIN( ID, CODE_NUMBER) VALUES( id,description);
dbms_output.put_line( id ||' '|| 'Already Exists');
EXCEPTION
WHEN DUP_VAL_ON_INDEX THEN
dbms_output.put_line( R_C1.variable);
END;
END LOOP;
END;
There's no need to do this with PL/SQL and cursors. What you really want to do is something like this:
MERGE INTO MAIN dst
USING (
SELECT regions.REGION_ID id,
regions.REGION_NAME description
FROM regions
) src
ON src.id = dst.id
WHEN MATCHED THEN UPDATE
SET dst.code_number = src.description
WHEN NOT MATCHED THEN INSERT (id, code_number)
VALUES (src.id, src.description)
Read more about the SQL MERGE statement in the documentation
I can not really see a point in doing a cursor in this case. Why can't you just do it like this:
--Update the rows
UPDATE MAIN
SET ID=regions.REGION_ID,
CODE_NUMBER=regions.[description]
FROM MAIN
JOIN regions
ON MAIN.ID=regions.REGION_ID;
--Insert the new ones
INSERT INTO MAIN(ID,CODE_NUMBER)
SELECT
regions.REGION_ID,
regions.[description]
FROM
regions
WHERE NOT EXISTS
(
SELECT
NULL
FROM
MAIN.ID=regions.REGION_ID
)