Mysql, combining and querying results with sub queries or temp tables - mysql

Question

I am running into some trouble with the following circumstances:
I have a query that creates two temp tables, and the following select to join them together--
SELECT * FROM result
INNER JOIN result2 ON result2.packetDetailsId = result.packetDetailsId
I am then trying to create another column from concatenating a few of the resulting fields and then use that to reference/query against another table. Is there a way to accomplish this in one query? Should I get away from the temp tables?
Thank you again in advance.
update: If I try to alias the combination of the two temp tables I get an error message stating [Err] 1060 - Duplicate column name 'packetDetailsId'
select * from (
SELECT * FROM result
INNER JOIN result2 ON result2.packetDetailsId = result.packetDetailsId) as myalias
Another Update: I almost have it working as one query but I get the result "(BLOB)" in the column I concoctenated:
select packet_details.packetDetailsId,products.productId,Credit,AccountNum,OrderStat, CONCAT(products.productId,Credit,'_',OrderStat) as consol from (
select packetDetailsId, GROUP_CONCAT(Credit) AS Credit, GROUP_CONCAT(AccountNum) AS AccountNum, GROUP_CONCAT(OrderStat) AS OrderStat FROM
( SELECT pd_extrafields.packetDetailsId,
CASE WHEN pd_extrafields.ex_title LIKE ('%Credit%')
THEN pd_extrafields.ex_value ELSE NULL END as Credit,
CASE WHEN pd_extrafields.ex_title LIKE ('%Account%')
THEN pd_extrafields.ex_value ELSE NULL END as AccountNum,
CASE WHEN pd_extrafields.ex_title LIKE ('%Existing%')
THEN pd_extrafields.ex_value ELSE NULL END as OrderStat
FROM pd_extrafields )AS TempTab GROUP BY packetDetailsId ) as alias2
INNER JOIN packet_details ON alias2.packetDetailsId = packet_details.packetDetailsId
INNER JOIN sales ON packet_details.packetDetailsId = sales.packetDetailsId
INNER JOIN sold_products ON sales.saleId = sold_products.saleId
INNER JOIN products ON sold_products.productId = products.productId

Answer 1

If I understand correctly, you already have the temporary tables created and you need to "concatenate" the results, using from ... inner join ...
The only possible restriction you may have is that you can only reference your temporary tables once in your from clause; besides that, there are no other restrictions (I frequently use temporary tables as intermediate steps in the creation of my final result).
Tips
Let's say your temp tables are temp_result1 and temp_result2. Both tables have a field packedDetailsId, on which the join will be performed. Remember to create the appropriate indexes on each table; at the very least you need to index packedDetailsId on both tables:
alter table temp_result1
add index PDI(packedDetailsId);
alter table temp_result2
add index PDI(packedDetailsId);
Now, just execute a query with the desired join and concatenation. If concat returns BLOB, then cast the result as char (of course, I'm assuming you need a text string):
select r1.*, r2.*, cast(concat(r1.field1, ',', r2.field2) as char) as data_concat
from temp_result1 as r1
inner join temp_result2 as r2 on r1.packedDetailsId = r2.packedDetailsId;
I see your problem is that GROUP_CONCAT is returning BLOB values... It's normal (MySQL doesn't know a priori how to return the values, so it returns binary data); just use the cast function.
Hope this helps you

Answer 2

so, if the result2 and result are both temp tables, you will have to include the # if local temp table and ## if global temp table
so your statements should be :
SELECT * FROM #result
INNER JOIN #result2 ON #result2.packetDetailsId = #result.packetDetailsId
My Bad. This is only applicable for MS SQL