0 - 23 of 23 tags for primary index

I downloaded this Geospatial Shapefile:
https://www2.census.gov/geo/tiger/TIGER2015/UAC/
 
The table that was created by loading the shapefile looks like this:

I have a transactional dataset which has a date field, my query is whether it is better to bring in the date field into the PI for the table i am using or leave it out. The PI is currently made up of a product unique identifier which is duplicated for each date related to the product.

Hi,
Is it possible to drop PI from an empty table in Teradata. Then load data into it and then recreate the PI to make the data load faster ?
Please advise.
Thanks,
Raj 

Hi All,

I am doing physical Database design in my project. LDM(3rd normal form relation model) is done and I am in the process of selecting primary index for the tables.

Hi all,
I was extending the partition of some tables to host the 2015 and I have notice this strange behavior.
I have this table called Table1

Hi All,
I have tables which are already created in DB. Almost half the tables are having more skewness. Now, I need to change PI for those tables which are having high skewness. Instead of checking each and every combination of columns manually, is there any way to check them at a stretch? I have nearly 200 tables.

I have created below table:
create table T1
(
col1 varchar (20)
,col2 int
,col3 varchar (10)
, primary key (col1, col2));
After creating this table while executing show select * from T1 I found no PI has been choosen by Teradata.
Will teradata treat this table as NOPI?

Hi All,
I am updating my tables based on primary index, however from the DBQL I see all the amps are active. Could someone explain, if this is expected ?
 
Cannot post the table structre for confidentialy reasons.
But it's like:
MyTable
(Column1 CHAR(10)
,Column2 CHAR(5)
,Column3 INTEGER
....

As volatile table definition does not go into DD, how Indexes and stats works on volatile table?

Hi All,
I am aware that order of columns in defined PI doesn't matter.
But if we have multilevel Partition defined on the table and we are including the partitioning columns as a part of PI, does it matter in anyway how the PPI columns be included in the PI of the table.
I hope I made myself clear.
 
Thanks!

Hello,
 
If i have column emp_id as an index. and if u use it in 'in' clause or exists clause will i get the beiifit of PI as in = clause
foe eg:
sel *  from table where emp_id in ( select id from table_b where <condition>)
*****
or 

Hi Teradatares :-)
I am new to Teradata database. Currently I am thiking of creating "big" table that should grow 200 mln rows each week. After a year data it will be 10 000 000 000 rows
After reading some best practice, documentation and forum, that's what I kind of understand.
Create table test

Hi All,
I have data in an csv file and I am planning to create an table in Teradata and insert these records.
I then need to create an PI after the analyzing the data properties.
I somehow need to know the queries for the following.
1) Get the data distribution among all the AMP's

Hi All,
    While creating a table if i specify both the Primary Index and Primary Key on the same column the table cretion fails.

This session provides information on the basic concepts of Partitioned Primary Indexes.

 
I have a time-series table with data points that are time periods. I'd like to be able to evaluate the following designs:
 
create multiset table dropme_t0(
  whatever_id varchar(50),
  data_point_start_dtm timestamp(0), -- in UTC
  data_point_end_dtm timestamp(0) )

Is it a good practice to define a Primary Index on VARCHAR column ? Although I dont see any strange (data type conversions) in explain plans between Join operations on VARCHAR (Primary Index) to CHAR column (Primary Index) since they are from same domain, I just want to understand if this is as efficient as Joins between CHAR to CHAR columns.

I have noticed that while creating a table, I can create Primary Keys using the following syntax :

CONSTRAINT name PRIMARY KEY (column1, column2....)

However if I pull up the SQL for table creation after the initial create, this becomes

UNIQUE PRIMARY INDEX name (column1, column2...)

This is more than an overview of the Indexes that are available in Teradata and how they work.

Hi,

How can I query for all the Primary Indexes that doesn't have statistics collected? (for all tables of all databases).

Thanks in advance,

Regards

Hi All,

I am a beginner on Teradata and am involved in an exploration to figure out what it would take to migrate an existing system based on Informatica PC+Oracle to Informatica PC+Teradata. I am trying to understand some guidelines or best practices in determining primary index for tables - I understand this is an optimization exercise to maximize data distribution while trying to use fewer columns, using those that are used for querying often are recommended.

The purpose of the new Teradata 13.0 feature that allows you to create tables with no primary index is improved performance of FastLoad and Teradata Parallel Data Pump Array INSERT data loading operations.