Nested joins in Teradata - response (1) by Raja_KT
Nested join provides one of the fastest performance compared to other joins, since it does not touch all amps to join tables. It works mostly with PI/SI. The WHERE clause uses an equijoin with a...
View ArticleTeradata architechtural behaviour - response (4) by Raja_KT
Hi Soumik, For AWT, you can have a look at this link http://developer.teradata.com/blog/carrie/2010/12/how-to-calculate-your-max-number-of-usable-amp-worker-tasks . Carrie has given a vivid...
View ArticleNested joins in Teradata - response (1) by Raja_KT
You posted in another one the same. I replied there. It seems the site, registers twice. It happens sometimes for me too. Cheers, Raja
View ArticleNested joins in Teradata - response (2) by M.Saeed Khurram
Hi, Nested joins are the most efficient join types used in Teradata. They are mostly useful with OLTP requests. In a nested join a row is selected from one table using an equality condition on PI or...
View ArticleRun time explain plan for a query - forum topic by pmehrotr
Iam using Teradata 14.x. I come from Oracle background. In Oracle, there are data dictionay views to look at explain plan" when query was actually exceuted which can be different from plan generated...
View ArticleRun time explain plan for a query - response (1) by Raja_KT
Hi, In oracle it is different and here it is different. You can have a look at DBC.DBQLExplainTbl . Also have a look at DBQLXMLTbl. I hope this is what you are looking for. Cheers, Raja
View ArticleCannot logon to the system - no access right to DBC.DatabaseV - forum topic...
Hello, In our system we have a few users created months ago. Now we have created a user for which all was set (ROLE, PROFILE, PASSWORD, ACCOUNT, etc…) but I cannot log-in with this user as the system...
View ArticleCreate back up tables using cursor - forum topic by mmanijay
Hi All, Im trying to automate the partitioning range for all tables in teradata. Is there any query for doing this. I need to take back up for all tables chnaging the table name '_bkp' added at the...
View ArticleGenerating Sequence Number when GROUP BY in the Query - forum topic by...
Hi, I have below requirement. I have many columns in the table and want to generate a sequence number using only one column. I am not able to use RANK() as I am using GROUP BY in my SQL. Is there any...
View ArticleGenerating Sequence Number when GROUP BY in the Query - response (1) by Raja_KT
Hi Pavan, You can't use OLAP and aggregates together. The workaround is to use derived table or temporary table. Try this:take your group by query inside. Rank the result from obtained from derived....
View ArticleDatamart - forum topic by samapika.t
Hi friend I am new to teradata.. Can anyone tell me what is datamart????????????????Forums: Database
View ArticleProblem with CASE WHEN statement - response (11) by atomhouse
Hi, I am facing an issue with the CASE statements. Please find below the case statement, CASE WHEN TYPE_CD IN ('01','02','03') THEN 1 WHEN TYPE_cD IN ('03') AND STS_CD='N' THEN 0 ELSE 0 END as CNT...
View ArticleProblem with CASE WHEN statement - response (12) by atomhouse
I mean, how do we do a IF-ELSE using case statement?
View ArticleProblem with CASE WHEN statement - response (13) by Raja_KT
Hi, CASE WHEN TYPE_cD IN ('03') AND STS_CD='N' THEN 0 WHEN TYPE_CD IN ('01','02','03') THEN 1 ELSE 0 END as CNT is your "if else" itself. I think you need to understand what is required and change...
View ArticleDatamart - response (1) by Raja_KT
Data mart is a special purpose subset of enterprise data for a particular function. It may contain detail or summary data or both. Data mart types: Independent- created directly from ods Logical- A...
View ArticleGenerating Sequence Number when GROUP BY in the Query - response (2) by dnoeth
Hi Sagar, of course you can use RANK and aggregates in the same query, OLAP functions are calculated after GROUP BY/HAVING. You probably use the deprecated RANK(col) instead of RANK() OVER (ORDER BY...
View ArticleQuery on Skew-Sensitivity in the TD12 above Optimizer - response (12) by...
Hi All I have not received any update on my above query. However, I found few things by myself. I am sharing that. Hope this might be helpful to others. 1. I create the below table. CREATE TABLE...
View ArticleProblem with CASE WHEN statement - response (14) by dnoeth
Hi Anu, the first WHEN in a CASE which evaluates to TRUE will be used, it's not doing a kind of best-match. The rule of thumb is to define the most restrictive condition first. You could rewrite it to:...
View ArticleDatamart - response (2) by dnoeth
Datamarts are not specific to Teradata: http://en.wikipedia.org/wiki/Datamart
View ArticleGenerating Sequence Number when GROUP BY in the Query - response (3) by Raja_KT
Oops, it is me who is with the older generation code. I used the deprecated one. I dont know from which version, this one supports. Thanks Dieter.
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