How to insert values to newly added column - oracle

I am new to oracle thus this question.
There is a table already existed and I have added a new column to it.
There are 5 rows and I do not want to use update table with where clause to insert the values one by one in the new column. Is there a statement like INSERT ALL to insert the values into the new column in one shot ?
Thanks

You can also use something like below which in-effect I would say is multiple update only, wrapped in single statement.
SQL> select * from test_upd;
ID1 ID2
---------- ----------
1
2
3
4
SQL> update test_upd a set a.id2 =
2 (select
3 case
4 when id1=1 then 100
5 when id1=2 then 200
6 when id1=3 then 300
7 else 5000 end
8 from test_upd b
9 where a.id1=b.id1);
4 rows updated.
SQL> select * from test_upd;
ID1 ID2
---------- ----------
1 100
2 200
3 300
4 5000

Use a MERGE statement:
MERGE INTO your_table dst
USING (
SELECT 1 AS id, 'aaa' AS newvalue FROM DUAL UNION ALL
SELECT 2, 'bbb' FROM DUAL UNION ALL
SELECT 3, 'ccc' FROM DUAL UNION ALL
SELECT 4, 'ddd' FROM DUAL UNION ALL
SELECT 5, 'eee' FROM DUAL
) src
ON (dst.id = src.id)
WHEN MATCHED THEN
UPDATE SET value = src.newvalue;
Which, if you have the table:
CREATE TABLE your_table (id, value) AS
SELECT 1, CAST(NULL AS VARCHAR2(3)) FROM DUAL UNION ALL
SELECT 2, NULL FROM DUAL UNION ALL
SELECT 3, NULL FROM DUAL UNION ALL
SELECT 4, NULL FROM DUAL UNION ALL
SELECT 5, NULL FROM DUAL;
Then, after the MERGE, the table contains:
ID
VALUE
1
aaa
2
bbb
3
ccc
4
ddd
5
eee
db<>fiddle here

Related

Extract Data Between Brackets in Oracle SQL

I have a table with data in below format
COURSE
[]
["12345"]
["12345","7890"
I want to extract the data between [] but without "
So, my output would be in below format
COURSE
12345
12345, 7890
I tried the below code which works fine for first 3 rows
select REGEXP_SUBSTR (COURSE,
'"([^"]+)"',
1,
1,
NULL,
1) from TEST;
But 4th row only results in 12345.
Why not simple translate?
SQL> with test (course) as
2 (select '[]' from dual union
3 select null from dual union
4 select '["12345"]' from dual union
5 select '["12345","7890"]' from dual
6 )
7 select course,
8 translate(course, 'a[]"', 'a') result
9 from test;
COURSE RESULT
---------------- -----------------------------------------
["12345","7890"] 12345,7890
["12345"] 12345
[]
SQL>

Sum 2 columns from multiple rows with same ID

Currently, I have a table MY_TABLE like below:
ID ACCT_TYPE CREDIT_AMT DEBIT_AMT
-- --------- ---------- ---------
1 CDT_01 4 (null)
1 DBT_01 (null) 6
One ID can have multiple ACCT_TYPE like above, and each type has its own amount.
I want to just select the row which has ACCT_TYPE like 'CDT_%' but also the total_amount column which is the total of credit_amt and debit_amt column for the same ID.
My expected output like below:
ID ACCT_TYPE TOTAL_AMT
-- --------- ---------
1 CDT_01 10
I tried with this select statement below but it's no use, I think it's because of different ACCT_TYPE:
Select ID, ACCT_TYPE, SUM(NVL(CREDIT_AMT, 0) + NVL(DEBIT_AMT, 0)) TOTAL_AMT
FROM MY_TABLE WHERE ACCT_TYPE LIKE 'CDT_%' GROUP BY ID, ACCT_TYPE;
Here is the output of the select statement above:
ID ACCT_TYPE TOTAL_AMT
-- --------- ---------
1 CDT_01 4
I just begin to learn some query so I don't know is it really possible to get my expected output.
One way to do it is like below:
with inputs (ID, ACCT_TYPE, CREDIT_AMT, DEBIT_AMT) as
(
select 1, 'CDT_01', 4, null from dual union all
select 1, 'DBT_01', null, 6 from dual
),
prep as
(
select t.*, sum(nvl(credit_amt,0)) over (partition by id) + sum(nvl(debit_amt,0)) over (partition by id) as sum_per_id
from inputs t
)
select id, acct_type, sum_per_id
from prep
where acct_type like 'CDT_%';
Output:
A correlated subquery might be one option; sample data (thank you, #Ranagal) in lines #1 - 5; query that does the job begins at line #6.
SQL> with inputs (ID, ACCT_TYPE, CREDIT_AMT, DEBIT_AMT) as
2 (
3 select 1, 'CDT_01', 4, null from dual union all
4 select 1, 'DBT_01', null, 6 from dual
5 )
6 select a.id,
7 a.acct_type,
8 (select sum(nvl(b.credit_amt, 0)) +
9 sum(nvl(b.debit_amt , 0))
10 from inputs b
11 where b.id = a.id
12 ) total_amt
13 from inputs a
14 where acct_type like 'CDT%';
ID ACCT_T TOTAL_AMT
---------- ------ ----------
1 CDT_01 10
SQL>

Select default in case of no value returned

I am trying to get some default value in my resultset if query does not return anything. I am trying nvl for the same but it is not returning the expected default value. To simulate, Consider following query,
select nvl(null, '10') from dual where 1=0;
I want to get 10 in case of given condition is not true and query does not return any value. However above query not returning any row.
Your query returns zero rows. NVL() isn't going to change that (*).
The correct solution is for the program which executes the query to handle NO_DATA_FOUND exception rather than fiddling the query.
However, you need a workaround so here is one using two sub-queries, one for your actual query, one to for the default.
When your_query returns an empty set you get this:
SQL> with your_qry as
2 ( select col1 from t42 where 1=0 )
3 , dflt as
4 ( select 10 as col1 from dual )
5 select col1
6 from your_qry
7 union all
8 select col1
9 from dflt
10 where not exists (select * from your_qry );
COL1
----------
10
SQL>
And when it returns a row you get this:
SQL> with your_qry as
2 ( select col1 from t42 )
3 , dflt as
4 ( select 10 as col1 from dual )
5 select col1
6 from your_qry
7 union all
8 select col1
9 from dflt
10 where not exists (select * from your_qry );
COL1
----------
12
13
SQL>
The WITH clause is optional here, it just makes it easier to write the query without duplication. This would have the same outcome:
select col1
from t42
where col0 is null
union all
select 10
from dual
where not exists (select col1
from t42
where col0 is null)
;
(*) Okay, there are solutions which use NVL() or COALESCE() with aggregations to do this. They work with single column projections in a single row as this question poses, but break down when the real query has more than one row and/or more than one column. Aggregations change the results.
So this looks alright ...
SQL> with cte as (
2 select 'Z' as col0, 12 as col1 from dual where 1=0 union all
3 select 'X' as col0, 13 as col1 from dual where 1=0 )
4 select
5 nvl(max(col0), 'Y') as col0, nvl(max( col1), 10) as col1
6 from cte;
COL0 COL1
---------- ----------
Y 10
SQL>
... but this not so much:
SQL> with cte as (
2 select 'Z' as col0, 12 as col1 from dual union all
3 select 'X' as col0, 13 as col1 from dual )
4 select
5 nvl(max(col0), 'Y') as col0, nvl(max( col1), 10) as col1
6 from cte;
COL0 COL1
---------- ----------
Z 13
SQL>
May be something like this is what you need
You could change WHERE clause (in this case WHERE COL > 1) similarly in both places.
WITH T(COL) AS(
SELECT 1 FROM DUAL UNION ALL
SELECT 2 FROM DUAL UNION ALL
SELECT 3 FROM DUAL
)
SELECT COL FROM T WHERE COL > 1
UNION ALL
SELECT 10 AS COL FROM DUAL WHERE NOT EXISTS( SELECT 1 FROM T WHERE COL > 1)
You can use aggregation. An aggregation query always returns one row:
select coalesce(max(null), '10')
from dual
where 1 = 0;
I prefer coalesce() to nvl() because coalesce() is the ANSI standard function. But, nvl() would work here just as well.

Getting Results in Horizontal way in oracle

I wrote query
select s_id from emp
where s_inv=12
i got results in this manner
1
2
3
4
5
but i want it in this format
1 2 3 4 5
If you need your result in a single column, you can use LISTAGG:
with emp(s_id, s_inv) as
(
select 1, 12 from dual union all
select 2, 12 from dual union all
select 3, 12 from dual union all
select 4, 12 from dual union all
select 5, 12 from dual
)
select listagg(s_id, ' ') within group (order by s_id)
from emp
where s_inv = 12
If you need to build many columns on the same row, you should first define how many columns will your result have

plsql: Getting another field values along with the aggregation values in a grouping statement

I am working on a time attendance system. I have the employees' transactions stored in the following table:
I want to get the earliest and the latest transactions for each employee including their date and type.
I am able to get the dates using grouping and aggregation. However, I am not able to figure out how to get types with them.
Would you please help me in it.
Thank you.
That's what the FIRST and LAST aggregate functions are designed for.
Here is a link to the documentation:
FIRST: http://download.oracle.com/docs/cd/E11882_01/server.112/e17118/functions065.htm#SQLRF00641
LAST: http://download.oracle.com/docs/cd/E11882_01/server.112/e17118/functions083.htm#sthref1206
And here is an example:
SQL> create table my_transactions (id,employee_id,action_date,type)
2 as
3 select 1, 1, sysdate, 'A' from dual union all
4 select 2, 1, sysdate-1, 'B' from dual union all
5 select 3, 1, sysdate-2, 'C' from dual union all
6 select 4, 1, sysdate-3, 'D' from dual union all
7 select 5, 2, sysdate-11, 'E' from dual union all
8 select 6, 2, sysdate-12, 'F' from dual union all
9 select 7, 2, sysdate-13, 'G' from dual
10 /
Table created.
SQL> select *
2 from my_transactions
3 order by id
4 /
ID EMPLOYEE_ID ACTION_DATE T
---------- ----------- ------------------- -
1 1 04-07-2011 10:15:07 A
2 1 03-07-2011 10:15:07 B
3 1 02-07-2011 10:15:07 C
4 1 01-07-2011 10:15:07 D
5 2 23-06-2011 10:15:07 E
6 2 22-06-2011 10:15:07 F
7 2 21-06-2011 10:15:07 G
7 rows selected.
SQL> select employee_id
2 , min(action_date) min_date
3 , max(type) keep (dense_rank first order by action_date) min_date_type
4 , max(action_date) max_date
5 , max(type) keep (dense_rank last order by action_date) max_date_type
6 from my_transactions
7 group by employee_id
8 /
EMPLOYEE_ID MIN_DATE M MAX_DATE M
----------- ------------------- - ------------------- -
1 01-07-2011 10:15:07 D 04-07-2011 10:15:07 A
2 21-06-2011 10:15:07 G 23-06-2011 10:15:07 E
2 rows selected.
Regards,
Rob.
You could try to use analytical(or windowing functions)
select *
from
(select id, employee_id, action_date,type,
max(action_date) over (partition by employee_id) max_action_date,
min(action_date) over (partition by employee_id) min_action_date
from transaction)
where action_date in (max_action_date, min_action_date)

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