Matching data in two tables

J

jet04

This is probably pretty rudimentary but I'm doing an Update Query in 2007 and
I am having an issue with my criteria.

I have two tables:
tbl_1 contains a column with a serial number (14,000 rows) .
tbl_2 contains a column with user description information that includes the
serial numbers I want to match. (45,000 rows)

tbl_1 field: 673567
tbl_2 field: FTN 673567 333, Doe John, W, X,

Here is my query in SQL:
UPDATE tbl_2, tbl_1
SET tbl_2.[Compare Match] = "Match"
WHERE (((tbl_2.Descriptor) Like '*' & [tbl_1]![Serial Number] & '*'));

I actually get this query to work with smaller data tables, but there seems
to be a conflict with the size of my two tables and the criteria I'm using to
do the match (200 rows against 14,000). Any ideas. This really should be
jumping out at me but it is not. Thanks.
 
T

Tom van Stiphout

Are you getting any errors?
I could see that this is slow,because you are creating a carthesian
product by selecting tbl_2, tbl1. That produces 14000 * 45000 results,
which you then join using a wildcard on both sides. Yes, that may take
a while...
If the serial number in tbl_2 is in a predictable location or has a
predictable format it may be better to pull it out first (e.g.
Mid$(Descriptor, 5, 6), store it in a temporary field, and then inner
join the two serialno fields.

-Tom.
Microsoft Access MVP
 
J

jet04

Tom,

No errors other than the query taking a long time, which you spoke to. The
join sounds like what i should have tried in the beginning due to the data
size, but was hoping magic would happen. Ha!

Thanks.
Are you getting any errors?
I could see that this is slow,because you are creating a carthesian
product by selecting tbl_2, tbl1. That produces 14000 * 45000 results,
which you then join using a wildcard on both sides. Yes, that may take
a while...
If the serial number in tbl_2 is in a predictable location or has a
predictable format it may be better to pull it out first (e.g.
Mid$(Descriptor, 5, 6), store it in a temporary field, and then inner
join the two serialno fields.

-Tom.
Microsoft Access MVP
This is probably pretty rudimentary but I'm doing an Update Query in 2007 and
I am having an issue with my criteria.
[quoted text clipped - 16 lines]
do the match (200 rows against 14,000). Any ideas. This really should be
jumping out at me but it is not. Thanks.
 
K

KARL DEWEY

Or instead of storing the results save the query and use it in another query
to join fields.

--
Build a little, test a little.


Tom van Stiphout said:
Are you getting any errors?
I could see that this is slow,because you are creating a carthesian
product by selecting tbl_2, tbl1. That produces 14000 * 45000 results,
which you then join using a wildcard on both sides. Yes, that may take
a while...
If the serial number in tbl_2 is in a predictable location or has a
predictable format it may be better to pull it out first (e.g.
Mid$(Descriptor, 5, 6), store it in a temporary field, and then inner
join the two serialno fields.

-Tom.
Microsoft Access MVP

This is probably pretty rudimentary but I'm doing an Update Query in 2007 and
I am having an issue with my criteria.

I have two tables:
tbl_1 contains a column with a serial number (14,000 rows) .
tbl_2 contains a column with user description information that includes the
serial numbers I want to match. (45,000 rows)

tbl_1 field: 673567
tbl_2 field: FTN 673567 333, Doe John, W, X,

Here is my query in SQL:
UPDATE tbl_2, tbl_1
SET tbl_2.[Compare Match] = "Match"
WHERE (((tbl_2.Descriptor) Like '*' & [tbl_1]![Serial Number] & '*'));

I actually get this query to work with smaller data tables, but there seems
to be a conflict with the size of my two tables and the criteria I'm using to
do the match (200 rows against 14,000). Any ideas. This really should be
jumping out at me but it is not. Thanks.
.
 

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