Consider I have 4 columns in a table and i have datas for 3 columns like below
TableTest
Col1 | Col2 | Col3
D11 | D12 |
D21 | D22 |
Normally the update query would be
Update TableTest SET Col1 = D11 , Col2 = D12 , COL3 = newdata Where Col1= D11
The Scenario is , the update query should only push data to the COL3 , it should skip the Col1 and Col2, as it has already filled with data(even if same or different data for the Col1 and Col2)
This might help -
UPDATE TableTest a
INNER JOIN TableTest b ON a.Col1 = b.Col1
SET a.Col3 = 'newData'
WHERE a.Col3 IS NULL
An INNER JOIN with the same table so that it updates the appropriate row!
NULL or blank value.If you just want to update COL3 than don't include other columns in UPDATE query.
Query:
Update TableTest SET COL3 = newdata Where Col1= D11
You should update whole table using single query as:
Update TableSet SET COL3=CONCAT('D',CONVERT(Substr(Col2,2),INT)+1)
This will update table as follows:
TableTest
Col1 | Col2 | Col3
D11 | D12 | D13
D21 | D22 | D23
Just do it, like this:
Update TableTest SET COL3 = newdata Where Col1= D11
In UPDATE query, there is no need to reassign the value of col1 and col2 if those values are not changing.
UPDATE TableTest
SET COL3 = newdata
WHERE Col1= 'D11';
.... SET Col2 = CASE WHEN Col2 = '' THEN 'newdata' ELSE Col2 END, ...... this assumes meaning of empty is''if null is empty or also expected you may need to modify theWHENaccordingly