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rivkamakFlag for United States of America

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update a field based off of another table

I have 1 table with a list of car makes and an ID.
then I have a list of models with a column for carid that matches the first table.

I was wondering  how I can update the model table and replace all the ids with the name from the make table where the makeid matches the other table.

Would something like this work?
update carmodels set carmodels.makeid = carmakes.carname where carmodels.makeid = carmakes.carid

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Avatar of ste5an
ste5an
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The T-SQL syntax is

UPDATE c
SET makeID = O.carName
FROM carmodels C
  INNER JOI carmakes M ON C.makeID = M.makeID;

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But why want you do this? You can use a JOIN anytime you need this information. Also it is semantically wrong, cause an ID is not a name. Thus this kind of update is not a good idea. It introduces also redundancy, which is a unwanted situation in the relational model, because it opens the model to get inconsistent.
1) You would not want to do that.  If you do want to put the name in the other table, you should create a corresponding column for it, not put a name into an "id" column.
2) I doubt you could put the full name in an id column anywhere.  Presumably the id column is either numeric or much shorter than the name value anyway.
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ASKER

Right now I am using 2 sql statmenets and I am trying to figure out how to combine it into 1.
select * from CarMakes where name= ' getname' and type='automobile'
then
select * from CarModels where makeid = '"  & (makeList.Fields.Item("carid").Value)  & "' order by model

can i do this with 1 join?
ASKER CERTIFIED SOLUTION
Avatar of Vitor Montalvão
Vitor Montalvão
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