I'm working with housing data with multiple columns. During the cleaning process, I noticed that there are some Null values ​​in the "PropertyAddress" column, and I wanted to confirm if these Null values ​​can be matched with the ParcelID. Therefore, I wrote the following query to confirm the previous assertion and display the results below the query.

SELECT a.ParcelID, a.PropertyAddress, b .ParcelID, b.PropertyAddress
FROM nashville_housing a
JOIN nashville_housing b
    on a.ParcelID = b.ParcelID
    AND a.UniqueID <> b.UniqueID
WHERE a.PropertyAddress is null;

After confirming that I can use ParcelID to change the Null value to the correct PropertyAddress, I wrote the UPDATE query:

UPDATE nashville_housing
SET PropertyAddress = ( 
SELECT a.ParcelID, b.PropertyAddress, b .ParcelID, b.PropertyAddress
FROM nashville_housing a
JOIN nashville_housing b
    on a.ParcelID = b.ParcelID
    AND a.UniqueID <> b.UniqueID
WHERE a.PropertyAddress is null);

But an error occurred "Error Code: 1241. Operand should contain 1 column(s)"

So, I rewrote the query as:

UPDATE a
SET PropertyAddress = IFNULL(a.PropertyAddress,b.PropertyAddress)
WHERE a.PropertyAddress is null;

But the error "Error Code: 1146. Table 'nasville_housing.a' doesn't exist"

Finally, I wrote:

UPDATE a
SET PropertyAddress = IFNULL(a.PropertyAddress,b.PropertyAddress) in (
SELECT a.ParcelID, b.PropertyAddress, b .ParcelID, b.PropertyAddress
FROM nashville_housing a
JOIN nashville_housing b
    on a.ParcelID = b.ParcelID
    AND a.UniqueID <> b.UniqueID
WHERE a.PropertyAddress is null);

But the error "Error Code: 1146. Table 'nasville_housing.a' doesn't exist"

I appreciate any support anyone can give me.