The MadRhino needs some advice on JOIN!

MadRhino

Hey Guys/Gals,

I have 2 tables with the exact same columns.

I want to "JOIN" the 2 together.

What would be the best way? Join, Union, Neither? Let me know, thanks!

laserlight

Well, the self-evident answer is that you want to join them, but clearly by "JOIN" you mean something else... are you trying to merge the two tables into one by copying the rows from one into the other?

MadRhino

Thanks for replying laser,

I need to combine both tables for a select query.

I was doing some homework and started getting a little confused and seconf guessing myself.

Table 1 is exactly the same as table 2. I need to have act as one table.

make sense? :o

Thanks!

laserlight

Table 1 is exactly the same as table 2.

Why are they exactly the same, and what exactly do you mean by "exactly the same"?

make sense?

No, it does not make sense to have tables that are "exactly the same" in the same database.

lazzerous

I think what you're looking for is a union.

If Table A and Table B have the same columns, but different data, you would do this:

SELECT fieldOne, fieldTwo FROM TableA WHERE foo='bar'
UNION ALL

SELECT fieldOne, fieldTwo FROM TableB WHERE foo='bar'

More info on UNIONs here: http://www.w3schools.com/sql/sql_union.asp

MadRhino

laserlight;10892272 wrote:
Why are they exactly the same, and what exactly do you mean by "exactly the same"?

No, it does not make sense to have tables that are "exactly the same" in the same database.

Ok,

I have 2 tables... same amount/name of columns, eg;

Table 1
agent_id, company_id, address, city, etc, etc

Table 2
agent_id, company_id, address, city, etc, etc

Why are they exactly the same?

Table 1 is populated via an external feed and only updates what it needs to.
Table 2 is populated via FTP/CSV where I have it truncate before updating.
And of course there are a few more reasons, but I do not need to go into detail.

I just want to merge both tables together, acting like one. eg:

When I do a SELECT *, I need to grab all the data from Table 1 and Table 2.

Did that help? :queasy:

lazzerous

SELECT FROM TableA
UNION ALL
SELECT FROM TableB

MadRhino

Thanks guys... much appreciated! Again, this forum is awesome!

laserlight

Yes, UNION ALL could be a solution here, but are you sure that it is not simply better to have both sources insert and update to the same table?

lazzerous

I agree with laserlight (When did you change your name?)

It would be more manageable with one table. Just add an additional field as a bit, and use it as a flag for where it was populated from, if you need to know.

MadRhino

Laser,

Well, I have 4 different feeds populating table 1, which is exactly what you are suggesting. Believe me, this what I wanted to do.

However, I had to separate the data in Table 2, because the files I get each evening is a complete file of listings. It would be much easier on me if only new listings were sent to me. If I updated just the one table each day, I would lose all listings from the other feeds. Very complicated

On top of that, there are other data that I need to update to match that of table 1.

I know this is just a temp fix. I am working on a something that will work much easier.

Thanks!