I am new in Oracle SQL and I am trying to make an update of a table with the next context:
I have a table A:
+---------+---------+---------+----------+
| ColumnA | name | ColumnC | Column H |
+---------+---------+---------+----------+
| 1 | Harry | null | null |
| 2 | Harry | null | null |
| 3 | Harry | null | null |
+---------+---------+---------+----------+
And a table B:
+---------+---------+---------+
| name | ColumnE | ColumnF |
+---------+---------+---------+
| Harry | a | d |
| Ron | b | e |
| Hermione| c | f |
+---------+---------+---------+
And I want to update the table A so that the result will be the next:
+---------+---------+---------+----------+
| ColumnA | name | ColumnC | Column H |
+---------+---------+---------+----------+
| 1 | Harry | a | d |
| 2 | Harry | a | d |
| 3 | Harry | a | d |
+---------+---------+---------+----------+
How could I do it?
merge into tableA a
using tableB b
on (a.name=b.name)
when matched then update set
columnC = b.columnE,
columnH = b.columnF
create table tableA (columnC varchar2(20), columnH varchar2(20), name varchar2(20), columnA number);
create table tableB (columnE varchar2(20), columnF varchar2(20), name varchar2(20));
insert into tableA values (null, null,'Harry',1);
insert into tableA values (null, null,'Harry',3);
insert into tableA values (null, null,'Harry',3);
insert into tableB values ('a', 'd','Harry');
insert into tableB values ('b', 'e','Ron');
insert into tableB values ('c', 'f','Hermione');
select * from tableA;
merge into tableA a
using tableB b
on (a.name=b.name)
when matched then update set
columnC = b.columnE,
columnH = b.columnF;
select * from tableA;
I got no error
UPDATE tableA t1
SET (ColumnC, ColumnH) = (SELECT t2.ColumnE, t2.ColumnF
FROM table2 t2
WHERE t1.name = t2.name)
WHERE EXISTS (
SELECT 1
FROM table2 t2
WHERE t1.name = t2.name)
This should work. You can refer to this answer for more info:
Oracle SQL: Update a table with data from another table
I think you can use below query and update your table A.
Update all rows with 'a' and 'd';
update table A
set (columnC , columnh ) = (SELECT COLUMNE,COLUMNF
FROM TABLE B
where b.name =a.name);
Alternatively you can also use:
UPDATE (SELECT T2.COLUMNE COLE,
T2.COLUMNF COLF,
T1.COLUMNC COLC,
T1.COLUMNH COLH
FROM tableB T2,
tableA T1
WHERE T1.NAME = T2.NAME)
SET COLC = COLE,
COLH = COLF ;
and Output is :
+---------+---------+---------+----------+
| ColumnA | name | ColumnC | Column H |
+---------+---------+---------+----------+
| 1 | Harry | a | d |
| 2 | Harry | a | d |
| 3 | Harry | a | d |
+---------+---------+---------+----------+
Related
I have following Store Procedure.
Declare #myData TABLE(
Id int,
Note1 nvarchar(Max),
Note2 nvarchar(Max),
Note3 nvarchar(Max),
)
Insert into #myData (Id,Note1,Note2,Note3)
Select
--First Column
E.Id as [ID],
E.Notes as [Note1],
E.NotesDate as [Date1]
F.ItemDescription as [Note2],
F.DescriptionDate as [Date2]
G.Description as [Note3],
G.DescDate as [Date3]
From
Employee E
LEFT Join Tab1 as F
on I.EmpId = E.Id
LEFT join Tab2 AS G
on G.EmpId = E.Id
where E.Id = 1019
select * from #myData
It gives Following result table.
+------+----------+------------+-------+-------------+---------+--------------+
| ID | Note1 | Date1 | Note2 | Date2 | Note3 | Date3 |
+------+----------+------------+-------+-------------+----------+-------------+
| 1 | admils | 2020-07-02 | sadd | 2020-06-08 | 1230 | 2020-05-06 |
+------+----------+--------+---------+---------------+----------+-------------+
Now i need resulting table some thing like below...
+------+----------+-------------+--------+
| ID | Note1 | Date | Col |
+------+----------+-------------+--------+
| 1 | admils | 2020-07-02 | 1 | <- Because This Data is from Note1 Column
| 1 | sadd | 2020-06-08 | 2 | <- Because This Data is from Note2 Column
| 1 | 1230 | 2020-05-06 | 3 | <- Because This Data is from Note3 Column
+------+----------+-------------+--------+
Just unpivot your data, as shown in the linked duplicate candidate. I prefer using VALUES over UNPIVOT as it's less restrictive:
SELECT E.ID,
V.[Description],
V.[Date],
V.Col
FROM dbo.Employee E
LEFT JOIN dbo.Tab1 T1 ON E.ID = T1.EmpID
LEFT JOIN dbo.Tab2 T2 ON E.ID = T2.EmpID
CROSS APPLY (VALUES(1,E.NotesDate,E.Notes),
(2,T1.DescriptionDate,T1.ItemDescription),
(3,T2.DescDate,T2.Description))V(Col,[Date],[Description]);
This question already has an answer here:
SQL Server : remove substring results from result set
(1 answer)
Closed 4 years ago.
SQL table has the following data, with 3 columns
Id,
Name and
Full Name.
| ID | Name | FullName |
| 1 | a | a |
| 2 | b | ab |
| 3 | c | abc |
| 4 | d | ad |
| 5 | e | ade |
| 6 | i | i |
| 7 | g | ig |
For example, in the rows where ID =1 and , Full Name column value(s) are 'a' and 'ab'. This data is a substring in the row 3 (id =3) Full Name column data 'abc'.
How to exclude the rows Id =1 and Id =2 because the 'full name' column data is a substring to the FullName column value 'abc' in row Id =3.
Desired output
| ID | Name | FullName |
| 3 | c | abc |
| 5 | e | ade |
| 7 | g | ig |
Here is a solution:
CREATE TABLE MyTable(
ID INT,
Name VARCHAR(45),
FullName VARCHAR(90)
);
INSERT INTO MyTable VALUES
(1, 'a', 'a'),
(2, 'b', 'ab'),
(3, 'c', 'abc'),
(4, 'd', 'ad'),
(5, 'e', 'ade'),
(6, 'i', 'i'),
(7, 'g', 'ig');
SELECT *
FROM MyTable
WHERE ID NOT IN (
SELECT DISTINCT T1.ID
FROM MyTable T1 INNER JOIN MyTable T2
ON T1.ID <> T2.ID
AND T2.FullName LIKE '%' + T1.FullName + '%'
);
Results:
+----+----+------+----------+
| | ID | Name | FullName |
+----+----+------+----------+
| 1 | 3 | c | abc |
| 2 | 5 | e | ade |
| 3 | 7 | g | ig |
+----+----+------+----------+
Here is a query which seems to be working. We can phrase a matching full name as one for which there are no parents of that full name.
SELECT t1.*
FROM yourTable t1
WHERE
NOT EXISTS (SELECT 1 FROM yourTable t2
WHERE t2.FullName LIKE '%' + t1.FullName + '%' AND
LEN(t2.FullName) > LEN(t1.FullName));
Demo
I have a table with a million records. I need to update some columns which are null based on the existing 'not null' records of a particular id based columns. I've tried with one query, it seems to be working fine but I don't have confidence in it that it will be able to update all those 1 million records exactly the way I need. I'm providing you some sample data how my table looks like.Any help will be appreciated
SELECT * INTO #TEST FROM (
SELECT 1 AS EMP_ID,10 AS DEPT_ID,15 AS ITEM_NBR ,NULL AS AMOUNT,NULL AS ITEM_NME
UNION ALL
SELECT 1,20,16,500,'ABCD'
UNION ALL
SELECT 1,30,17,NULL,NULL
UNION ALL
SELECT 2,10,15,1000,'XYZ'
UNION ALL
SELECT 2,30,16,NULL,NULL
UNION ALL
SELECT 2,40,17,NULL,NULL
) AS A
Sample data:
+--------+---------+----------+--------+----------+
| EMP_ID | DEPT_ID | ITEM_NBR | AMOUNT | ITEM_NME |
+--------+---------+----------+--------+----------+
| 1 | 10 | 15 | NULL | NULL |
| 1 | 20 | 16 | 500 | ABCD |
| 1 | 30 | 17 | NULL | NULL |
| 2 | 10 | 15 | 1000 | XYZ |
| 2 | 30 | 16 | NULL | NULL |
| 2 | 40 | 17 | NULL | NULL |
+--------+---------+----------+--------+----------+
Expected result:
+--------+---------+----------+--------+----------+
| EMP_ID | DEPT_ID | ITEM_NBR | AMOUNT | ITEM_NME |
+--------+---------+----------+--------+----------+
| 1 | 10 | 15 | 500 | ABCD |
| 1 | 20 | 16 | 500 | ABCD |
| 1 | 30 | 17 | 500 | ABCD |
| 2 | 10 | 15 | 1000 | XYZ |
| 2 | 30 | 16 | 1000 | XYZ |
| 2 | 40 | 17 | 1000 | XYZ |
+--------+---------+----------+--------+----------+
I tried this but I'm unable to conclude whether it is updating all the 1 million records properly.
SELECT * FROM #TEST T
inner JOIN #TEST T1 ON T1.EMP_ID=T.EMP_ID
WHERE T1.AMOUNT IS NOT NULL
UPDATE T SET AMOUNT=T1.AMOUNT
FROM #TEST T
inner JOIN #TEST T1 ON T1.EMP_ID=T.EMP_ID
WHERE T1.AMOUNT IS not NULL
I have used UPDATE using inner join
UPDATE T
SET T.AMOUNT = X.AMT,T.ITEM_NME=X.I_N
FROM #TEST T
JOIN
(SELECT EMP_ID,MAX(AMOUNT) AS AMT,MAX(ITEM_NME) AS I_N
FROM #TEST
GROUP BY EMP_ID) X ON X.EMP_ID = T.EMP_ID
SELECT * into #Test1
FROM #TEST
WHERE AMOUNT IS NOT NULL
For records validation run this query first
SELECT T.AMOUNT, T1.AMOUNT, T1.EMP_ID,T1.EMP_ID
FROM #TEST T
inner JOIN #TEST1 T1 ON T1.EMP_ID=T.EMP_ID
WHERE T.AMOUNT IS NULL
Begin Trans
UPDATE T
SET T.AMOUNT=T1.AMOUNT, T.ITEM_NME= = T1.ITEM_NME
FROM #TEST T
inner JOIN #TEST1 T1 ON T1.EMP_ID=T.EMP_ID
WHERE T.AMOUNT IS NULL
rollback
SELECT EMP_ID,MAX(AMOUNT) as AMOUNT MAX(ITEM_NAME) as ITEM_NAME
INTO #t
FROM #TEST
GROUP BY EMP_ID
UPDATE t SET t.AMOUNT = t1.AMOUNT, t.ITEM_NAME = t1.ITEM_NAME
FROM #TEST t INNER JOIN #t t1
ON t.emp_id = t1.emp_id
WHERE t.AMOUNT IS NULL and t.ITEM_NAME IS NULL
Use MAX aggregate function to get amount and item name for each employee and then replace null values of amount and item name with those values. For validation use COUNT function to calculate the number of rows with values of amount and item name as null. If the number of rows is zero then table is updated correctly
I have a postgresql schema with two tables:
tableA: tableB:
| id | username | | fk_id | resource |
| 1 | user1 | | 2 | item1 |
| 2 | user1 | | 1 | item3 |
| 3 | user1 | | 1 | item2 |
| 4 | user2 | | 4 | item5 |
| 5 | user2 | | 5 | item8 |
| 6 | user3 | | 3 | item9 |
The foreign key fk_id in tableB references id in tableA.
How can I update all of the foreign key id's of tableB to point to the lowest entry for a unique username in tableA?
update table_b b
set fk_id = d.id
from table_a a
join (
select distinct on (username) username, id
from table_a
order by 1, 2
) d using(username)
where a.id = b.fk_id;
Test it here.
The query used inside the update gives actual_id, username, desired_id:
select a.id actual_id, username, d.id desired_id
from table_a a
join (
select distinct on (username) username, id
from table_a
order by 1, 2
) d using(username)
actual_id | username | desired_id
-----------+----------+------------
1 | user1 | 1
2 | user1 | 1
3 | user1 | 1
4 | user2 | 4
5 | user2 | 4
6 | user3 | 6
(6 rows)
We define your tables:
CREATE TABLE tableA (id, username) AS
SELECT * FROM
(
VALUES
(1, 'user1'),
(2, 'user1'),
(3, 'user1'),
(4, 'user2'),
(5, 'user2'),
(6, 'user2')
) AS x ;
CREATE TABLE tableB (fk_id, resource) AS
SELECT * FROM
(
VALUES
(2, 'item1'),
(1, 'item3'),
(1, 'item2'),
(4, 'item5'),
(5, 'item8'),
(3, 'item9')
) AS x ;
With that info, you can create a (virtual) conversion table, and use it to update your data:
-- Using tableA, make a new table with the
-- minimum id for every username
WITH username_to_min_id AS
(
SELECT
min(id) AS min_id, username
FROM
tableA
GROUP BY
username
)
-- Convert the previous table to a id -> min_id
-- conversion table
, id_to_min_id AS
(
SELECT
id, min_id
FROM
tableA
JOIN username_to_min_id USING(username)
)
-- Use this conversion table to update tableB
UPDATE
tableB
SET
fk_id = min_id
FROM
id_to_min_id
WHERE
-- JOIN condition with table to update
id_to_min_id.id = tableB.fk_id
-- Take out the ones that won't change
AND (fk_id <> min_id)
RETURNING
* ;
The result you would get is:
+-------+----------+----+--------+
| fk_id | resource | id | min_id |
+-------+----------+----+--------+
| 1 | item1 | 2 | 1 |
| 1 | item9 | 3 | 1 |
| 4 | item8 | 5 | 4 |
+-------+----------+----+--------+
Shows you that three rows have been updated, that had fk_id = (2, 3, 5), and have now (1, 1, 4). (The id is the "old" fk_id value).
You can check it at http://rextester.com/EQPH47434
You can "squeeze everything" [change every virtual table name by its definition, and do a couple of SELECT optimizations] and get this equivalent query (probably less clear, yet totally equivalent):
UPDATE
tableB
SET
fk_id = min_id
FROM
tableA
JOIN
(
SELECT
min(id) AS min_id, username
FROM
tableA
GROUP BY
username
) AS username_to_min_id
USING (username)
WHERE
tableA.id = tableB.fk_id
AND (fk_id <> min_id)
RETURNING
* ;
I have a table with three columns with double values, but no double rows. Now I want to split this table in two table with unique values and a link table. I think the Problem gets clearer when I Show you example tables:
Original:
| ID | Column_1 | Column_2 | Column_3 |
|----|----------|----------|----------|
| 1 | A | 123 | A1 |
| 2 | A | 123 | A2 |
| 3 | B | 234 | A2 |
| 4 | C | 456 | A1 |
Table_1
| ID | Column_1 | Column_2 |
|----|----------|----------|
| 1 | A | 123 |
| 2 | B | 234 |
| 3 | C | 456 |
Table_2
| ID | Column_3 |
|----|----------|
| 1 | A1 |
| 2 | A2 |
Link-Table
| ID | fk1 | fk2 |
|----|-----|-----|
| 1 | 1 | 1 |
| 2 | 1 | 2 |
| 3 | 2 | 2 |
| 4 | 3 | 1 |
Table_1 I created like this:
INSERT INTO Table_1(Column_1, Column_2)
SELECT DISTINCT Column_1, Column_2 FROM Original
WHERE Original.Column_1 NOT IN (SELECT Column_1 FROM Table_1)
Table_2 I created in the same way.
The question now is, how to create the Link-Table?
The original table does grow continuesly, so only new entries should be added.
Do I have to use a Cursor, or is there a better way?
SOLUTION:
MERGE Link_Table AS LT
USING (SELECT DISTINCT T1.ID AS T1ID, T2.ID AS T2ID FROM Original AS O
INNER JOIN Table_1 AS T1 ON T1.Column_1 = O.Column_1
INNER JOIN Table_2 AS T2 ON T2.Column_3 = O.Column_3) AS U
ON LT.fk1 = U.T1ID
WHEN NOT MATCHED THEN
INSERT (fk1, fk2)
VALUES (U.T1ID, U.T2ID);
You can JOIN all 3 tables to get proper data for link table:
--INSERT INTO [Link-Table]
SELECT t1.ID,
t2.ID
FROM Original o
INNER JOIN Table_1 t1
ON t1.Column_1 = o.Column_1
INNER JOIN Table_2 t2
ON t2.Column_3 = o.Column_3
If your original table will grow, then you need to use MERGE to update/insert new data.
You have to inner join your Original,Table_1 and Table_2 to get the desired result.
Try like this, Its similar to gofr1 post.
DECLARE #orginal TABLE (
ID INT
,Column_1 VARCHAR(10)
,Column_2 INT
,Column_3 VARCHAR(10)
)
DECLARE #Table_1 TABLE (
ID INT
,Column_1 VARCHAR(10)
,Column_2 INT
)
DECLARE #Table_2 TABLE (
ID INT
,Column_3 VARCHAR(10)
)
Insert into #orginal values
(1,'A',123,'A1')
,(2,'A',123,'A2')
,(3,'B',234,'A2')
,(4,'C',456,'A1')
Insert into #Table_1 values
(1,'A',123)
,(2,'B',234)
,(3,'C',456)
Insert into #Table_2 values
(1,'A1')
,(2,'A2')
SELECT O.ID
,T1.ID
,T2.ID
FROM #orginal O
INNER JOIN #Table_1 T1 ON T1.Column_1 = O.Column_1
INNER JOIN #Table_2 T2 ON T2.Column_3 = O.Column_3