insert all and inner join in oracle - oracle

I would like to insert data in to two tables. Will be one-to-many connection. For this, I have to use Foreign Key, of course.
I think, table1 - ID column is an ideal for this a Primary Key. But I generate it always with a trigger, automatically, every line. SO,
How can I put Table1.ID (auto generated, Primary Key) column in to table2.Fkey column in the same insert query?
INSERT ALL INTO table1 ( --here (before this) generated the table1.id column automatically with a trigger.
table1.food,
table1.drink,
table1.shoe
) VALUES (
'apple',
'water',
'slippers'
)
INTO table2 (
fkey,
color
) VALUES (
table1.id, -- I would like table2.fkey == table1.id this gave me error
'blue'
) SELECT
*
FROM
table1
INNER JOIN table2 ON table1.id = table2.fkey;
The error message:
"00904. 00000 - "%s: invalid identifier""

As suggested by #OldProgrammer, use sequence
INSERT ALL INTO table1 ( --here (before this) generated the table1.id column automatically with a trigger.
table1_id,
table1.food,
table1.drink,
table1.shoe
) VALUES (
<sequecename_table1>.nextval,
'apple',
'water',
'slippers'
)
INTO table2 (
fkey,
color
) VALUES (
<sequecename_table2>.nextval,
<sequecename_table1>.currval, -- returns the current value of a sequence.
'blue'
) SELECT
*
FROM
table1
INNER JOIN table2 ON table1.id = table2.fkey;

Since you're using Oracle DB's 12c version, then might use Identity Column Property. Then easily return the value of first table's (table1) to a local variable by charging of returning clause just after an insert statement for table1, and use inside the next insert statement which is for table2 as stated below :
SQL> create table table1(
2 ID integer generated always as identity primary key,
3 food varchar2(50), drink varchar2(50), shoe varchar2(50)
4 );
SQL> create table table2(
2 fkey integer references table1(ID),
3 color varchar2(50)
4 );
SQL> declare
2 cl_tab table1.id%type;
3 begin
4 insert into table1(food,drink,shoe) values('apple','water','slippers' )
5 returning id into cl_tab;
6 insert into table2 values(cl_tab,'blue');
7 end;
8 /
SQL> select * from table1;
ID FOOD DRINK SHOE
-- ------- ------- -------
1 apple water slippers
SQL> select * from table2;
FKEY COLOR
---- --------------------------------------------------
1 blue
Anytime you issue the above statement for insertions between begin and end, both table1.ID and table2.fkey columns will be populated by the same integer values. By the way do not forget to commit the changes by insertions, if you need these values throughout the DB(i.e.from other sessions also).

Related

Copy from VARCHAR field to NUMBER field such that VARCHAR value becomes null after being copied to NUMBER field

I have two tables Table1 and Table2 both with the same columns TestResult and Testcounts. Table1 has testresult as varchar and Table2 has testresult as number.
I have a string .for eg "Oracle" as value for testresult of varchar type for Table1 which needs to be inserted to testresult of number type of Table2 as null.How can i do this? Any suggestions will be highly appreciated :)
EDIT
I have table1 with columns as TestResult varchar2(50) and Testcount number with values as "0.5","0.6","0.8","Oracle" for TestResult and 1,2,3,4 for Testcount.
Now i have another table Table2 as TestResult number and Testcount number with no values, in other words its empty.. I would like to insert all data from table1 to table2 with "Oracle" being inserted as "null"
The following will do what you've asked for:
INSERT INTO TABLE2 (TESTRESULT, TESTCOUNTS)
SELECT CASE
WHEN LENGTH(REGEXP_SUBSTR(TESTRESULT, '[0-9.]*')) = LENGTH(TESTRESULT) THEN TESTRESULT
ELSE NULL
END,
TESTCOUNTS
FROM TABLE1
SQLFiddle here
If you only have a single string value that you can't convert to a number, and you want to set that to null, you can just use a case expression to supply the null:
insert into table2 (testresult, testcounts)
select case when testresult = 'Oracle' then null else to_number(testresult) end,
testcounts
from table1;
Demo:
create table table1 (testresult varchar2(10), testcounts number);
insert into table1
select '0.5', 1 from dual
union all select '0.6', 2 from dual
union all select '0.8', 3 from dual
union all select 'Oracle', 4 from dual;
create table table2 (testresult number, testcounts number);
insert into table2 (testresult, testcounts)
select case when testresult = 'Oracle' then null else to_number(testresult) end,
testcounts
from table1;
select * from table2;
TESTRESULT TESTCOUNTS
---------- ----------
.5 1
.6 2
.8 3
4
db<>fiddle
If you are using Oracle 12c Release 2 (or above) you could also just try to convert the string to a number and use the default ... on conversion error clause to substitute null for that, or any other, non-numeric value:
insert into table2 (testresult, testcounts)
select to_number(testresult default null on conversion error), testcounts
from table1;
select * from table2;
TESTRESULT TESTCOUNTS
---------- ----------
.5 1
.6 2
.8 3
4
In earlier versions you could do the same thing with a user-defined function that wraps the real to_number() call and returns null on error. Or a regex/translate check similar to what #BobJarvis has shown.
Having multiple rows with null would make the data hard to interpret though, so hopefully you only have this one fixed value...

Convert String List to Number in Oracle DB

I am saving table ids as foreign key into another table using Oracle Apex Shuttle field like(3:4:5). Now I want to use these IDS in sql query using IN Clause. I have replaced : with , using replace function but it shows
no data found
message.
The following query works fine when I use static values.
select * from table where day_id IN(3,4,5)
But when I try to use
select * from table where id IN(Select id from table2)
it shows no data found.
From what i understand you have a list like 1:2:3:4 that you want to use in a IN clause; you can transform the list into separated values like this:
select regexp_substr('1:2:3:4','[^:]+', 1, level) as list from dual
connect by regexp_substr('1:2:3:4', '[^:]+', 1, level) is not null;
This will return:
List
1
2
3
4
Then you can simply add it to your query like this:
SELECT *
FROM TABLE
WHERE day_id IN
(SELECT regexp_substr('1:2:3:4','[^:]+', 1, level) AS list
FROM dual
CONNECT BY regexp_substr('1:2:3:4', '[^:]+', 1, level) IS NOT NULL
);
Can you try below statement. It has working as you expected.
create table table1 (id number, name varchar2(20));
alter table table1 add constraints pri_cons primary key(id);
create table table2 (id number, name varchar2(20));
alter table table2 add constraints ref_cons FOREIGN KEY(id) REFERENCES table1 (id);
begin
insert into table1 values (1,'Bala');
insert into table1 values (2,'Sathish');
insert into table1 values (3,'Subbu');
insert into table2 values (1,'Nalini');
insert into table2 values (2,'Sangeetha');
insert into table2 values (3,'Rubini');
end;
/
select * from table1 where id IN (Select id from table2);

MERGING DATA OF TWO TABLES

I want to write a query which finds the difference between two tables and writes updates or new data into third table. My two tables have identical column names. Third table which captures changes have extra column called comment. I would like to insert the comment whether it is a new row or updated row based on the row modification.
**TABLE1 (BACKUP)**
KEY,FIRST_NAME,LAST_NAME,CITY
1,RAM,KUMAR,INDIA
2,TOM,MOODY,ENGLAND
3,MOHAMMAD,HAFEEZ,PAKISTAN
4,MONIKA,SAM,USA
5,MIKE,PALEDINO,USA
**TABLE2 (CURRENT)**
KEY,FIRST_NAME,LAST_NAME,CITY
1,RAM,KUMAR,USA
2,TOM,MOODY,ENGLAND
3,MOHAMMAD,HAFEEZ,PAKISTAN
4,MONIKA,SAM,INDIA
5,MIKE,PALEDINO,USA
6,MAHELA,JAYA,SL
**TABLE3 (DIFFERENCE FROM TABLE2 TO TABLE1)**
KEY,FIRST_NAME,LAST_NAME,CITY,COMMENT
1,RAM,KUMAR,USA,UPDATE
4,MONIKA,SAM,INDIA,UPDATE
6,MAHELA,JAYA,SL,INSERT
table scripts
DROP TABLE TABLE1;
DROP TABLE TABLE2;
DROP TABLE TABLE3;
CREATE TABLE TABLE1
(
KEY NUMBER,
FIRST_NAME VARCHAR2(100),
LAST_NAME VARCHAR2(100),
CITY VARCHAR2(50)
);
/
CREATE TABLE TABLE2
(
KEY NUMBER,
FIRST_NAME VARCHAR2(100),
LAST_NAME VARCHAR2(100),
CITY VARCHAR2(50)
);
/
CREATE TABLE TABLE3
(
KEY NUMBER,
FIRST_NAME VARCHAR2(100),
LAST_NAME VARCHAR2(100),
CITY VARCHAR2(50),
COMMENTS VARCHAR2(200)
);
/
INSERT ALL
INTO TABLE1
VALUES(1,'RAM','KUMAR','INDIA')
INTO TABLE1 VALUES(2,'TOM','MOODY','ENGLAND')
INTO TABLE1 VALUES(3,'MOHAMMAD','HAFEEZ','PAKISTAN')
INTO TABLE1 VALUES(4,'MONIKA','SAM','USA')
INTO TABLE1 VALUES(5,'MIKE','PALEDINO','USA')
SELECT 1 FROM DUAL;
/
INSERT ALL
INTO TABLE2
VALUES(1,'RAM','KUMAR','USA')
INTO TABLE2 VALUES(2,'TOM','MOODY','ENGLAND')
INTO TABLE2 VALUES(3,'MOHAMMAD','HAFEEZ','PAKISTAN')
INTO TABLE2 VALUES(4,'MONIKA','SAM','INDIA')
INTO TABLE2 VALUES(5,'MIKE','PALEDINO','USA')
INTO TABLE2 VALUES(6,'MAHELA','JAYA','SL')
SELECT 1 FROM DUAL;
I was using the merge statement to accomplish the same. but i have hit a roadblock in merge statement , it's rhrowing an error "SQL Error: ORA-00905: missing keyword
00905. 00000 - "missing keyword"" I dont understand where is the error. please help
INSERT INTO TABLE3
SELECT KEY,FIRST_NAME,LAST_NAME,CITY,NULL AS COMMENTS FROM TABLE2
MINUS
SELECT KEY,FIRST_NAME,LAST_NAME,CITY,NULL AS COMMENTS FROM TABLE1
;
MERGE INTO TABLE3 A
USING TABLE1 B
ON (A.KEY=B.KEY)
WHEN MATCHED THEN
UPDATE SET A.COMMENTS='UPDATED'
WHEN NOT MATCHED THEN
UPDATE SET A.COMMENTS='INSERTED';
There is no such WHEN NOT MATCHED THEN UPDATE clause, you should use WHEN NOT MATCHED THEN INSERT. Refer to MERGE for details.
A few assumptions made about the data:
An INSERT event will be a record identified by its key in table2 (current data) that does not have a matching key in the original back-up table: table1.
An UPDATE event is a field that exists in both table1 and table2 for the same KEY but is not the same.
Records which did not change between tables are not to be recorded in table3.
Example Query: Check for Updates
SELECT UPD_QUERY.NEW_CITY, 'UPDATED' as COMMENTS
FROM (SELECT CASE WHEN REPLACE(CURR.CITY, BKUP.CITY,'') IS NOT NULL THEN CURR.CITY
ELSE NULL END as NEW_CITY
FROM table1 BKUP, table2 CURR
WHERE BKUP.KEY = CURR.KEY) UPD_QUERY
WHERE UPD_QUERY.NEW_CITY is NOT NULL;
You can repeat this comparison method for the other fields:
SELECT UPD_QUERY.*
FROM (SELECT CURR.KEY,
CASE WHEN REPLACE(CURR.FIRST_NAME, BKUP.FIRST_NAME,'') IS NOT NULL
THEN CURR.FIRST_NAME
ELSE NULL END as FIRST_NAME,
CASE WHEN REPLACE(CURR.LAST_NAME, BKUP.LAST_NAME,'') IS NOT NULL
THEN CURR.LAST_NAME
ELSE NULL END as LAST_NAME,
CASE WHEN REPLACE(CURR.CITY, BKUP.CITY,'') IS NOT NULL
THEN CURR.CITY
ELSE NULL END as CITY
FROM table1 BKUP, table2 CURR
WHERE BKUP.KEY = CURR.KEY) UPD_QUERY
WHERE COALESCE(UPD_QUERY.FIRST_NAME, UPD_QUERY.LAST_NAME, UPD_QUERY.CITY)
is NOT NULL;
NOTE: This could get unwieldy very quickly if the number of columns compared are many. Since the target table design (table3) requires not only identification of a change, but the field and its new value are also recorded.
Example Query: Look for Newly Added Records
SELECT CURR.*, 'INSERTED' as COMMENTS
FROM table2 CURR, table1 BKUP
WHERE CURR.KEY = BKUP.KEY(+)
AND BKUP.KEY is NULL;
Basically MERGE forces the operation: MATCHED=UPDATE (or DELETE), NOT MATCHED = INSERT. It's in the docs.
You can do what you want but you need two insert statements with different set operators,
For UPDATED:
Insert into table3
table1 INTERSECT table2
For INSERTED:
Insert into table3
table2 MINUS table1

How to display comma separated descriptions based on comma separated values in Oracle 10g?

I am new to Oracle technology. Earlier I posted 2 posts for the same issue due to lack of understanding the requirement.
Table 1:
MSGID
-----
1,2,3
2,3
4
null
null
Table 2:
MID MSGDESC
---- -------
1 ONE
2 TWO
3 THREE
4 FOUR
Expected output:
XCOL DESC
----- -----
1,2,3 ONE,TWO,THREE
2,3 TWO,THREE
4 FOUR
I am not able to fulfil this requirement. Please provide me one solution.
Note: tables don't have any unique or primary key values. Table 1 has 5000 records and table 2 only has 80 records with descriptions.
create table Table1 (MSGID varchar2(100));
insert into Table1 values ('1,2,3');
insert into Table1 values ('2,3');
insert into Table1 values ('4');
insert into Table1 values (null);
insert into Table1 values (null);
create table Table2 (MID varchar2(100), MSGDESC varchar2(100));
insert into Table2 values ('1','ONE');
insert into Table2 values ('2','TWO');
insert into Table2 values ('3','THREE');
insert into Table2 values ('4','FOUR');
select
msgid as xcol,
"DESC",
col1, col2, ..., col12
from
Table1
left join (
select
msgid,
wm_concat(msgdesc) as "DESC"
from
(
select
msgid,
msgdesc
from
(select distinct msgid from Table1 where ...)
cross join (
select level as occ from dual connect by level <= 100)
)
left join Table2
on mid = regexp_substr(msgid, '[^,]+', 1, occ)
where
occ <= regexp_count(msgid, ',') + 1
order by msgid, occ
)
group by msgid
) using (msgid)

Oracle: how to INSERT if a row doesn't exist

What is the easiest way to INSERT a row if it doesn't exist, in PL/SQL (oracle)?
I want something like:
IF NOT EXISTS (SELECT * FROM table WHERE name = 'jonny') THEN
INSERT INTO table VALUES ("jonny", null);
END IF;
But it's not working.
Note: this table has 2 fields, say, name and age. But only name is PK.
INSERT INTO table
SELECT 'jonny', NULL
FROM dual -- Not Oracle? No need for dual, drop that line
WHERE NOT EXISTS (SELECT NULL -- canonical way, but you can select
-- anything as EXISTS only checks existence
FROM table
WHERE name = 'jonny'
)
Assuming you are on 10g, you can also use the MERGE statement. This allows you to insert the row if it doesn't exist and ignore the row if it does exist. People tend to think of MERGE when they want to do an "upsert" (INSERT if the row doesn't exist and UPDATE if the row does exist) but the UPDATE part is optional now so it can also be used here.
SQL> create table foo (
2 name varchar2(10) primary key,
3 age number
4 );
Table created.
SQL> ed
Wrote file afiedt.buf
1 merge into foo a
2 using (select 'johnny' name, null age from dual) b
3 on (a.name = b.name)
4 when not matched then
5 insert( name, age)
6* values( b.name, b.age)
SQL> /
1 row merged.
SQL> /
0 rows merged.
SQL> select * from foo;
NAME AGE
---------- ----------
johnny
If name is a PK, then just insert and catch the error. The reason to do this rather than any check is that it will work even with multiple clients inserting at the same time. If you check and then insert, you have to hold a lock during that time, or expect the error anyway.
The code for this would be something like
BEGIN
INSERT INTO table( name, age )
VALUES( 'johnny', null );
EXCEPTION
WHEN dup_val_on_index
THEN
NULL; -- Intentionally ignore duplicates
END;
I found the examples a bit tricky to follow for the situation where you want to ensure a row exists in the destination table (especially when you have two columns as the primary key), but the primary key might not exist there at all so there's nothing to select.
This is what worked for me:
MERGE INTO table1 D
USING (
-- These are the row(s) you want to insert.
SELECT
'val1' AS FIELD_A,
'val2' AS FIELD_B
FROM DUAL
) S ON (
-- This is the criteria to find the above row(s) in the
-- destination table. S refers to the rows in the SELECT
-- statement above, D refers to the destination table.
D.FIELD_A = S.FIELD_A
AND D.FIELD_B = S.FIELD_B
)
-- This is the INSERT statement to run for each row that
-- doesn't exist in the destination table.
WHEN NOT MATCHED THEN INSERT (
FIELD_A,
FIELD_B,
FIELD_C
) VALUES (
S.FIELD_A,
S.FIELD_B,
'val3'
)
The key points are:
The SELECT statement inside the USING block must always return rows. If there are no rows returned from this query, no rows will be inserted or updated. Here I select from DUAL so there will always be exactly one row.
The ON condition is what sets the criteria for matching rows. If ON does not have a match then the INSERT statement is run.
You can also add a WHEN MATCHED THEN UPDATE clause if you want more control over the updates too.
Using parts of #benoit answer, I will use this:
DECLARE
varTmp NUMBER:=0;
BEGIN
-- checks
SELECT nvl((SELECT 1 FROM table WHERE name = 'john'), 0) INTO varTmp FROM dual;
-- insert
IF (varTmp = 1) THEN
INSERT INTO table (john, null)
END IF;
END;
Sorry for I don't use any full given answer, but I need IF check because my code is much more complex than this example table with name and age fields. I need a very clear code. Well thanks, I learned a lot! I'll accept #benoit answer.
In addition to the perfect and valid answers given so far, there is also the ignore_row_on_dupkey_index hint you might want to use:
create table tq84_a (
name varchar2 (20) primary key,
age number
);
insert /*+ ignore_row_on_dupkey_index(tq84_a(name)) */ into tq84_a values ('Johnny', 77);
insert /*+ ignore_row_on_dupkey_index(tq84_a(name)) */ into tq84_a values ('Pete' , 28);
insert /*+ ignore_row_on_dupkey_index(tq84_a(name)) */ into tq84_a values ('Sue' , 35);
insert /*+ ignore_row_on_dupkey_index(tq84_a(name)) */ into tq84_a values ('Johnny', null);
select * from tq84_a;
The hint is described on Tahiti.
you can use this syntax:
INSERT INTO table_name ( name, age )
select 'jonny', 18 from dual
where not exists(select 1 from table_name where name = 'jonny');
if its open an pop for asking as "enter substitution variable" then use this before the above queries:
set define off;
INSERT INTO table_name ( name, age )
select 'jonny', 18 from dual
where not exists(select 1 from table_name where name = 'jonny');
You should use Merge:
For example:
MERGE INTO employees e
USING (SELECT * FROM hr_records WHERE start_date > ADD_MONTHS(SYSDATE, -1)) h
ON (e.id = h.emp_id)
WHEN MATCHED THEN
UPDATE SET e.address = h.address
WHEN NOT MATCHED THEN
INSERT (id, address)
VALUES (h.emp_id, h.address);
or
MERGE INTO employees e
USING hr_records h
ON (e.id = h.emp_id)
WHEN MATCHED THEN
UPDATE SET e.address = h.address
WHEN NOT MATCHED THEN
INSERT (id, address)
VALUES (h.emp_id, h.address);
https://oracle-base.com/articles/9i/merge-statement
CTE and only CTE :-)
just throw out extra stuff. Here is almost complete and verbose form for all cases of life. And you can use any concise form.
INSERT INTO reports r
(r.id, r.name, r.key, r.param)
--
-- Invoke this script from "WITH" to the end (";")
-- to debug and see prepared values.
WITH
-- Some new data to add.
newData AS(
SELECT 'Name 1' name, 'key_new_1' key FROM DUAL
UNION SELECT 'Name 2' NAME, 'key_new_2' key FROM DUAL
UNION SELECT 'Name 3' NAME, 'key_new_3' key FROM DUAL
),
-- Any single row for copying with each new row from "newData",
-- if you will of course.
copyData AS(
SELECT r.*
FROM reports r
WHERE r.key = 'key_existing'
-- ! Prevent more than one row to return.
AND FALSE -- do something here for than!
),
-- Last used ID from the "reports" table (it depends on your case).
-- (not going to work with concurrent transactions)
maxId AS (SELECT MAX(id) AS id FROM reports),
--
-- Some construction of all data for insertion.
SELECT maxId.id + ROWNUM, newData.name, newData.key, copyData.param
FROM copyData
-- matrix multiplication :)
-- (or a recursion if you're imperative coder)
CROSS JOIN newData
CROSS JOIN maxId
--
-- Let's prevent re-insertion.
WHERE NOT EXISTS (
SELECT 1 FROM reports rs
WHERE rs.name IN(
SELECT name FROM newData
));
I call it "IF NOT EXISTS" on steroids. So, this helps me and I mostly do so.

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