I need to create a new table from old one, need to insert the rows from the old one, only change is the new sequence column needs to be added in the new one.
Can someone please help me for the same?
INSERT INTO dps_session_map (TrackSESSION_SEQ,session_seq, column3)
SELECT
A.SEQ_Session.NEXTVAL, sm.session_seq, sm.column3
FROM
dps_session_map A,
dps_exec_session_map sm
WHERE sm.session_seq is not null;
Remove the VALUES keyword and its brackets:
--general pattern of inserting from one table to another existing table
INSERT INTO table(columns)
SELECT columns FROM othertable
Column count and type must match (or be implicitly convertible)
If your new table doesn't exist, do:
CREATE TABLE x AS
(SELECT columns FROM othertable)
INSERT INTO dps_session_map (TrackSESSION_SEQ,session_seq, column3)
SELECT
**SCHEMA.**SEQ_Session.NEXTVAL, sm.session_seq, sm.column3
FROM
dps_session_map A,
dps_exec_session_map sm
WHERE sm.session_seq is not null;
Reference the sequence by its name or fully qualified schema.name. Sequences don't belong to table. Are you getting a "ORA-02289: sequence does not exist" error?
Related
I created three tables A (id, name, date, realnumber, integer), B (id, name, date, realnumber, integer), and C which is identical to table A. It only has two more columns called integerB and sequence s. I want to create a trigger which would fire after insert on table B for each row input so that it saves the referenced row of Table A and adds integer from input row of table B in column integerB of table C. If the row already exists in Table C only integerB should be added. When it comes to sequence s, next value is added with first insert of row of table A.
Simple explanation: Table C is a copy of table A with two additional columns: integerB and sequence. The point of the trigger is to add new rows from table A without repetition, integerB from table B(integer in table B) and sequence should start with 1 and increment by 1. If the row in table A is repeated then only integerB should be updated.
I did not work with triggers that much, so I am not sure how to solve the problem when I have to insert data from multiple tables. Here is my trigger.
CREATE OR REPLACE TRIGGER trig1
AFTER INSERT ON B
FOR EACH ROW
INSERT INTO C (integerB) VALUES (NEW.integer);
INSERT INTO C (id, name, date, realnumber)
SELECT a.id, a.name, a.date, a.realnumber FROM A a;
END;
/
First off you really need to use better column and table names as a lot of these are reserved words... This makes everything far more complicated than it needs to be.
It isn't entirely clear what you want to do but it seems that if someone was to insert a record with ID = 1 into B then you want to get the values from A for ID = 1 and store them in C along with the integer value inserted into B
In which case you want to use an MERGE statement (UPSERT) in your trigger and something like
CREATE OR REPLACE TRIGGER T1
AFTER INSERT ON B
FOR EACH ROW
BEGIN
MERGE INTO C C
USING (SELECT * FROM A WHERE ID = :NEW.ID) A
ON (C.ID = :NEW.ID)
WHEN MATCHED THEN UPDATE
SET C.INTEGERB = :NEW.INTEGER,
C.SEQUENCE = C.SEQUENCE + 1
WHEN NOT MATCHED THEN
INSERT (ID, NAME, DATE, REALNUMBER, INTEGER, INTEGERB, SEQUENCE)
VALUES (A.ID, A.NAME. A.DATE, A.REALNUMBER, A.INTEGER, :NEW.INTEGER, 0);
END;
/
For sequence this has been set to 0 when a new record is inserted into C and then incremented each time integerB is updated. I am not sure if this is waht you want or not.
You should be able to tweak this to match the exact joins and logic you need.
Tip
Get your SQL statement working with literal values first and then translate it into your trigger. It will be much easier if you can get something working manually first before you attempt to make things more complicated
I am trying to replace all of the NULL values to 0 in a column of a big table in HIVE.
However, every time I try to implement some code I end up generating a new column to the table. The column I am trying to change/modify still exists and still has the NULL values but the new column that is automatically generated (i.e. _c1) is what I want the column I am trying to modify, to look like.
I tried to run a COALESCE but that also ended up generating a new column. I also tried to implement a CASE WHEN, but the same results ensued.
Select *,
CASE WHEN columnname IS NULL THEN 0
ELSE columnname
END
from tablename;
Also tried
SELECT coalesce(columnname, CAST(0 AS BIGINT)) FROM tablename
I would just like to update the table with the other columns being as is but the column I want to modify still has its original name but instead of NULL values it has 0's that replaced them.
I don't want to generate a new column but modify an existing one.
How should I do that?
Use insert overwrite .. option.
insert overwrite table tablename
select c1,c2,...,coalesce(columnname,0) as columnname
from tablename
Note that you have to specify all the other column names required in select.
I have a table in which I want unique identifier to be added automatically as a new record is inserted into it. Considering I have column for unique identifier already created.
hive can't update the table but you can create a temporary table or overwrite your first table.
you can also use concat function to join the two diferent column or string.
here is the examples
function :concat(string A, string B…)
return: string
hive> select concat(‘abc’,'def’,'gh’) from dual;
abcdefgh
HQL &result
insert overwrite table stock select tradedate,concat('aa',tradetime),stockid ,buyprice,buysize ,sellprice,sellsize from stock;
20130726 aa094251 204001 6.6 152000 6.605 100
20130726 aa094106 204001 6.45 13400 6.46 100
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
I have two tables:
create table Number( num number(5));
create table Entry(id number(3), name varchar(50));
How can I increment the num field of Number table in Oracle whenever I insert something in the Entry table?
You should use a SEQUENCE instead. The "Number" table is an inherently bad idea, because when two sessions are inserting rows concurrently, each session only sees the uncommited value in the Number table.
This is what you should do instead:
create sequence entrySeq;
create table Entry(id number(3), name varchar(50));
create trigger tr_entry before insert on Entry for each row
begin
select entrySeq.nextval into :new.number from dual;
end;
/
Do you want number.num to continually represent the number of rows iin the Entry table? If so you could just define it as a view:
create view number_view
as
select count(*) from Entry
create sequence entrySeq;
create table Entry(id number(3), name varchar(50));
insert into Entry value (entrySeq.nextval, 'MyName');
(You don't need a trigger).
A sequence returns a unique and increasing number value but Oracle doesn't guarantuee that it is gapless. When sometimes transactions are rollbacked the values of column id will contain gaps.