I want to create a procedure to remove all special characters from a column of my spesific table and then remove duplicate records.
I tried the following query so far to show the desired logic :
SELECT ft_nm_val,count(*)
FROM ( SELECT REGEXP_REPLACE(ft_nm_val, '[^A-Za-z0-9, ]') AS ft_nm_val
FROM fraud_token_name )
GROUP BY ft_nm_val
HAVING COUNT(*) > 1
Since you want to remove duplicate records and if there are other columns exist in the table, then concept duplicate would change row-wisely. So, I assume you have that table with only one column mentioned. Then you can create such a procedure :
SQL> create or replace procedure make_unique is
begin
--# Leave only alpha-numeric characters through applying [^ ] to [:alnum:] posix
update fraud_token_name
set ft_nm_val = regexp_replace(ft_nm_val,'[^[:alnum:]]');
--# Then delete duplicate records
delete fraud_token_name f1
where rowid <
(
select max(rowid)
from fraud_token_name f2
where f2.ft_nm_val = f1.ft_nm_val
);
commit;
end;
/
SQL> exec make_unique;
Demo
Related
I have a requirement that I need to insert row number in a table based on value already present in the table. For example, the max row_nbr record in the current table is something like this:
+----------+----------+------------+---------+
| FST_NAME | LST_NAME | STATE_CODE | ROW_NBR |
+----------+----------+------------+---------+
| John | Doe | 13 | 123 |
+----------+----------+------------+---------+
Now, I need to insert more records, with given FST_NAME and LST_NAME values. ROW_NBR needs to be generated while inserting the data into table with values auto-incrementing from 123.
I can't use a sequence, as my loading process is not the only process that inserts data into this table. And I can't use a cursor as well, as due to high volume of data the TEMP space gets filled up quickly. And I'm inserting data as given below:
insert into final_table
( fst_name,lst_name,state_code)
(select * from staging_table
where state_code=13);
Any ideas how to implement this?
It sounds like other processes are finding the current maximum row_nbr value and incrementing it as they do single-row inserts in a cursor loop.
You could do something functionally similar, either finding the maximum in advance and incrementing it (if you're already running this in a PL/SQL block):
insert into final_table (fst_name, lst_name, state_code, row_nbr)
select st.*, variable_holding_maximum + rownum
from staging_table st
where st.state_code=13;
or by querying the table as part of the query, which doesn't need PL/SQL:
insert into final_table (fst_name, lst_name, state_code, row_nbr)
select st.*, (select max(row_nbr) from final_table) + rownum
from staging_table st
where st.state_code=13;
db<>fiddle
But this isn't a good solution because it doesn't prevent clashes from different processes and sessions trying to insert at the same time; but neither would the cursor loop approach, unless it is catching unique constraint errors and re-attempting with a new value, perhaps.
It would be better to use a sequence, which would be an auto-increment column but you said you can't change the table structure; and you need to let the other processes continue to work without modification. You can still do that with a sequence and trigger approach, having the trigger always set the row_nbr value form the sequence, regardless of whether the insert statement supplied a value.
If you create a sequence that starts from the current maximum, with something like:
create sequence final_seq start with <current max + 1>
or without manually finding it:
declare
start_with pls_integer;
begin
select nvl(max(row_nbr), 0) + 1 into start_with from final_table;
execute immediate 'create sequence final_seq start with ' || start_with;
end;
/
then your trigger could just be:
create trigger final_trig
before insert on final_table
for each row
begin
:new.row_nbr := final_seq.nextval;
end;
/
Then your insert ... select statement doesn't need to supply or even think about the row_nbr value, so you can leave it as you have it now (except I'd avoid select * even in that construct, and list the staging table columns explicitly); and any existing inserts that do supply the row_nbr don't need to be modified and the value they supply will just be overwritten from the sequence.
db<>fiddle showing inserts with and withouth row_nbr specified.
Oracle - Alter all table column names with trim of white space in between names
For suppose column names before alter :
Home number
Mobile number
Local number
After alter column names shall be :
Homenumber
Mobilenumber
Localnumber
I've tried this way: but unable to crack:
UPDATE SA_VW_PHONENUMBER TN SET TN.Column_Name = TRIM (TN.Column_Name);
Fully automatic way
Use this cursor based DDL hacking - statement concat.
BEGIN
FOR alters IN
(
SELECT
'ALTER TABLE "'||table_name||'" RENAME COLUMN "'||column_name||
'" TO "'||replace(cols.column_name,' ','')||'"' sql_stmt
FROM all_tab_cols cols
WHERE REGEXP_LIKE(column_name,'[[:space:]]')
AND owner = user --Add real schema name here
ORDER BY 1
) LOOP
DBMS_OUTPUT.PUT_LINE ( alters.sql_stmt ||';') ;
EXECUTE IMMEDIATE alters.sql_stmt;
END LOOP;
END;
/
If you want to use the safe way
As I know you cannot perform a DDL as a dynamic SQL, so you cannot pass variables to the ALTER TABLE command, but here is what you can do instead of that.
Selecting the occurences:
SELECT table_name,column_name,replace(cols.column_name,' ','') as replace_name
FROM all_tab_cols
WHERE REGEXP_LIKE(column_name,'[[:space:]]');
Use the ALTER TABLE DDL command:
alter table T_TABLE rename column "COLUMN SPACE" TO "COLUMNNOSPACE";
Try the REPLACE function
UPDATE SA_VW_PHONENUMBER TN SET TN.Column_Name = REPLACE(TN.Column_Name,' ','')
I am new to Oracle. I have a table in Oracle which has 4 columns Period, Open_Flag,Creation_Dt,Updated_By.
The Period column is the Primary key of the table. I have created a proc which will check the value of period from input parameter in the table, if its existing, the value of Open_flag has to be updated else a new record shall be inserted.
create or replace
PROCEDURE PROC_REF_SAP_PERIOD(
V_PERIOD IN NUMBER,V_OPEN_FLAG IN VARCHAR2,V_CREATION_DT IN DATE,V_UPDATED_BY IN VARCHAR2)
AS
BEGIN
MERGE INTO REF_SAP_PERIOD T
USING (SELECT * FROM REF_SAP_PERIOD WHERE PERIOD=V_PERIOD )S
ON (T.PERIOD=S.PERIOD )
WHEN MATCHED THEN UPDATE SET OPEN_FLAG = V_OPEN_FLAG --WHERE PERIOD=V_PERIOD AND CREATION_DT=V_CREATION_DT AND UPDATED_BY=V_UPDATED_BY
WHEN NOT MATCHED THEN INSERT (PERIOD,OPEN_FLAG,CREATION_DT,UPDATED_BY) VALUES (V_PERIOD,V_OPEN_FLAG,V_CREATION_DT,V_UPDATED_BY);
END;
The issue is that the Update is working well in this case, however, the insert is not working. Please help.
You are merging table with itself, filtered by period. Obviously, it will never see your non-existent values in itself.
Try this line instead of your USING line:
using (select V_PERIOD "period" from dual)S
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
We are trying to modify the precision on existing columns in the database. Those which have been defined as NUMBER, we want to change it to NUMBER(14,2).
But, since NUMBER has a default precision of 38, there exist values in the database which run into more than 10 decimal places. So, when we create an additional column and try to copy over from a temp table, this results in errors.
select count(*) into countCol from USER_TAB_COLUMNS where TABLE_NAME = 'EVAPP_INTERFACE' and COLUMN_NAME = 'RESERVE_RATE_NUM' and DATA_SCALE is null;
IF (countCol <> 0) then
execute immediate 'alter table EVAPP_INTERFACE add RESERVE_RATE_NUM_TMP NUMBER(6,3)' ;
execute immediate 'update EVAPP_INTERFACE set RESERVE_RATE_NUM_TMP = RESERVE_RATE_NUM' ;
execute immediate 'alter table EVAPP_INTERFACE drop column RESERVE_RATE_NUM' ;
execute immediate 'alter table EVAPP_INTERFACE rename column RESERVE_RATE_NUM_TMP to RESERVE_RATE_NUM' ;
DBMS_OUTPUT.put_line('This column EVAPP_INTERFACE.RESERVE_RATE_NUM has been modified to the required precision');
Is there any way to truncate all values in a column?
Like say a column has
43.8052201822
21.1610909091
76.4761223618
75.8535613657
I want them all changed to
43.8
21.16
76.47
75.85
EDIT : I know the word Truncate is used wrongly, but I don't know of a better term to shaving off precision.
Not a wrong word at all, see: TRUNC(number).
From the example below you can see the difference of truncating and rounding:
create table foo(n number);
insert all
into foo values (1.111)
into foo values (5.555)
into foo values (9.999)
select * from dual;
select n, round(n,2), trunc(n, 2) from foo;
N ROUND(N,2) TRUNC(N,2)
---------- ---------- ----------
1.111 1.11 1.11
5.555 5.56 5.55
9.999 10 9.99
How about using ROUND (number)?