How do you update multiple fields from another table in mysql? - mysql

Question

This is the query I'm trying to accomplish:
update amdashboard
set (ASCID, ASCFirst, ASCLast, ASCOtherName, ASCAdd1, ASCAdd2,
ASCCity, ASCState, ASCZip, ASCZip4, ASCY2007, ASCY2008, ASCY2009,
ASCY2010, ASCY2011, ASCY2012, ASCEthnicity, ASCGender, ASCMaritalStatus)
= (select id, firstname, lastname, listingspousename, add1, add2,
city, state, zip, zip4, y2007, y2008, y2009,
y2010, y2011, y2012, Ethnicity, Gender, MaritialStatus
from ASCNCOAClean
inner join amdashboard
on ASCNCOAClean.firstname = amdashboard.actorsfirst
and ascncoaclean.lastname = amdashboard.actorslast)
where exists (select id, firstname, lastname, listingspousename,
add1, add2, city, state, zip, zip4, y2007, y2008,
y2009, y2010, y2011, y2012, Ethnicity, Gender,
MaritialStatus
from ASCNCOAClean
inner join amdashboard
on ASCNCOAClean.firstname = amdashboard.actorsfirst
and ascncoaclean.lastname = amdashboard.actorslast);
I can't get this to work...receiving a syntax error on the first parenthesis. So, I figured I'd try on just one field. I tried this:
update amdashboard
set ascid = (select ascncoaclean.id
from ASCNCOAClean
where ASCNCOAClean.firstname = amdashboard.actorsfirst
and ascncoaclean.lastname = amdashboard.actorslast)
where exists (select ascncoaclean.id
from ASCNCOAClean
where ASCNCOAClean.firstname = amdashboard.actorsfirst
and ascncoaclean.lastname = amdashboard.actorslast);
This however returns and error 1242: Subquery returns more than 1 row. That seems silly. I know it's going to return more than one row...I want it to because I need to update multiple rows.
What am I missing?

Answer 1

The query you want would look something like this:
UPDATE amdashboard a, ASCNCOAClean b SET
a.ASCID = b.id,
a.ASCFirst = b.firstname,
a.ASCLast = b.lastname,
a.ASCOtherName = b.listingspousename,
...
a.ASCMaritalStatus = b.MaritialStatus
WHERE a.actorsfirst = b.firstname;
Observe you will have to replace ... with the rest of the column associations I didn't write.
But be careful with that, something tells me this query is going to do something very wrong to your database, because you are not relating the tables using a unique key. If there are two records with the same ASCNCOAClean.firstname you certainly will have loss of data.
Also observe that it is going to update existing records on amdashboard, not add new ones. If your intention is to migrate data from ASCNCOAClean to amdashboard, assuming amdashboard is a brand new, empty table, then the query you want is this:
INSERT INTO amdashboard (
ASCID, ASCFirst, ASCLast, ASCOtherName, ASCAdd1, ASCAdd2, ASCCity, ASCState,
ASCZip, ASCZip4, ASCY2007, ASCY2008, ASCY2009, ASCY2010, ASCY2011, ASCY2012,
ASCEthnicity, ASCGender, ASCMaritalStatus
)
SELECT
id, firstname, lastname, listingspousename, add1, add2, city, state,
zip, zip4, y2007, y2008, y2009, y2010, y2011, y2012, Ethnicity, Gender,
MaritialStatus
FROM ASCNCOAClean;