Reputation: 11
I have a history table and I need to select the values from this table in ColumnName, ColumnValue form. I am using SQL Server 2008 and I wasn’t sure if I could use the PIVOT function to accomplish this. Below is a simplified example of what I need to accomplish:
This is what I have:
The table’s schema is
CREATE TABLE TABLE1 (ID INT PRIMARY KEY, NAME VARCHAR(50))
The “history” table’s schema is
CREATE TABLE TABLE1_HISTORY(
ID INT,
NAME VARCHAR(50),
TYPE VARCHAR(50),
TRANSACTION_ID VARCHAR(50))
Here is the data from TABLE1_HISTORY
ID NAME TYPE TRANSACTION_ID
1 Joe INSERT a
1 Bill UPDATE b
1 Bill DELETE c
I need to extract the data from TABLE1_HISTORY into this format:
TransactionId Type ColumnName ColumnValue
a INSERT ID 1
a INSERT NAME Joe
b UPDATE ID 1
b UPDATE NAME Bill
c DELETE ID 1
c DELETE NAME Bill
Other than upgrading to Enterprise Edition and leveraging the built in change tracking functionality, what is your suggestion for accomplishing this task?
Upvotes: 1
Views: 6961
Reputation: 247810
This can be done with the UNPIVOT
function in SQL Server:
select transaction_id,
type,
ColumnName,
ColumnValue
from
(
select transaction_id,
type,
cast(id as varchar(50)) id,
name
from TABLE1_HISTORY
) src
unpivot
(
ColumnValue
for ColumnName in (ID, Name)
) un
Upvotes: 1
Reputation: 58491
You could try using a UNION
Test Data
DECLARE @TABLE1_HISTORY TABLE (
ID INT,
NAME VARCHAR(50),
TYPE VARCHAR(50),
TRANSACTION_ID VARCHAR(50))
INSERT INTO @TABLE1_HISTORY
SELECT 1, 'Joe', 'INSERT', 'a'
UNION ALL SELECT 1, 'Bill', 'UPDATE', 'b'
UNION ALL SELECT 1, 'Bill', 'DELETE', 'c'
SQL Statement
SELECT [TransactionID] = Transaction_ID
, [Type] = [Type]
, [ColumnName] = 'ID'
, [ColumnValue] = CAST(ID AS VARCHAR(50))
FROM @Table1_History
UNION ALL
SELECT [TransactionID] = Transaction_ID
, [Type] = [Type]
, [ColumnName] = 'NAME'
, [ColumnValue] = [Name]
FROM @Table1_History
ORDER BY TransactionID
, ColumnName
Upvotes: 1