batch updating of Database Table data in Mysql
HiI have two tables.
tbl1
id int(11) NOT NULL
positionName varchar(20) NULL
positionId int(11) NULL
tbl2
positionId int(11) NOT NULL
positionName varchar(20) NULL
Originally, there is no column positionId
in tbl1
. Now will use positionId
instead of positionName
for tbl1
.
The problem is there are over thousands of data already stored in both tables.
So, How can I successfully and quickly link to the correct positionId
for the each data of tbl1
, in which position开发者_如何学运维Name
was previously used?
Is batch updating is a way?
Is there anyway that I can perform all things with SQL browser? If possible, I don't want to use coding.
Thanks ahead.
Are you looking for a multiple-table UPDATE
, like this?
UPDATE tbl1
JOIN tbl2 ON tbl1.positionName = tbl2.positionName
SET tbl1.positionId = tbl2.positionId
WHERE tbl1.positionId IS NULL
I'm assuming that positionName
is unique in tbl2
, but if it isn't, you'll need to consider how you wish to handle that.
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