From the forums. Getting row counts Wolfgang, Studio Sorry for the delay. Teradata Recent comments. Studio I am not aware of any problems with loading a volatile table. New opportunities for statistics collection in Teradata Related Training. It explores the product ca After watching this presen Overview Articles Reference Training.
Because the information needed to decipher password-protected item values in the wallet is never saved, the password protection scheme is considered to be more secure than the saved-key protection scheme. The saved-key protection scheme enciphers item values with a key that is derived from a user-supplied encryption passphrase. In summary, after the system is rebooted, the user must resupply the wallet password before accessing password-protected item values, but need not supply the wallet password before accessing saved-key-protected item values.
It is worthwhile to take note of distinctions between the secret information used by the two protection schemes. The password protection scheme uses a secret referred to as the wallet password. It is very important for the user to remember the wallet password; if the wallet password is lost, password-protected item values cannot be accessed.
Users are running scripted applications: They can embed password retrieval syntax into scripts instead of compromising security by including a password. Users are retrieving multiple Teradata Database systems: They can inevitably reclaim the correct password for a system instead of having to think of the password or look it up. All users log in to the similar client machine using the same login info and as such are frozen as the same user on the client system AND each user has a detached Teradata Database user name and password.
Your email address will not be published. Enter desired value for the item named "com. Item named "com. Us3r T3st. BTEQ Author: Atul Singh. For example. Then the buffer is dispatcehd to different threads to process data match schema, split fields etc? Load operator is the one really interesting here. Then how does the 2 load operator works? If not so, how does the multiple instance of load operator helps the load performance? In the case of the "file reader", multiple instances can be used to read from the same file to help boost performance.
Each instance reads the entire file, but sends only a subset of rows to the loading operator since most data is variable in length, it would be pretty difficult to have each instance reading a separate area of the file because each instance would not know where the row boundaries are. So, if you have 2 file reader instances, both instances will read all of the data, but instance 1 will send rows 1, 3, 5, 7, etc. For the loading operator i. Load, Update or Stream , each instance helps parallelize the loading of the data by pulling data out of the data streams.
TPT does not push the data through the data streams in a round-robin fashion. The data will flow to the first instance of the loading operator and if that operator instance can keep up with the rate at which the data is coming through the data streams, then that instance will get all of the work.
Only when the data stream queue for one instance becomes backed up will data be sent to the next instance instance 2. So, it is possible depending on the amount of data and the speed at which the data is produced onto the data stream for some instances to get no work at all. We cannot tell you the optimum number of instances to use because it depends on a LOT of factors.
Try a load job with a lot of data with one instance for the loading operator. Then increase the instance count to 2, then to 3. Take a look at the log for the loading instance and it will tell you how many rows were processed for each instance. You can then get an idea for the optimum number for that load job. I doubt you would ever need more than 3 or 4. The loading operators are pretty fast.
It is important to note that when you provide the max session count to the operator, that number is divided by the number of instances and each instance will connect a subset of that maximum. So, if you set MaxSessions to 30 and you have 2 instances of the Update operator, each instance will connect 15 sessions. If you have 3 instances, each instance will connect 10 sessions. And if you find that instance 3 is getting very little work, it might be a waste of resources to have that 3rd instance.
So, picking the number of instances is a delicate balancing act between resource utiliziation sessions, CPU, memory, processes, etc. And also note that even though you are using multiple instances of the Load or Update operator, to Teradata it looks like a single FastLoad or MultiLoad job.
I do want a little drill down into the loader. It looks to me that the update loader consumer still logon as a single mload job. Is that a correct understanding?
Yes, your understanding is correct on both replies. Having multiple processes work in parallel on the data takes advantage of multiple CPUs. And yes, it only helps the acquisition phase. The application phase is performed solely on the DBS side and the client application just waits for the DBS to finish.
Are you talking about the legacy utilities just asking because this is a TPT thread? However, you can always call each utility from a batch or Perl script. But you must be asking for a specific reason. Maybe if you elaborated on the reasons behind the questions, I could answer them better. We enjoyed your article and you are right - TPT is an excellent tool and one that TD probably doesn't understand its full potential.
Because TPT is 'object oriented', the environment we created basically generates object definitions for all load types and operators for every table TD and our sources. From the library, we select the specific objects, assemble them and then run with supplied parameters. Hi, I am new to TPT. I have created a job for loading data to Teradata table from a comma delimited flat file.
An AccountId string is optional information that is sometimes specified when an account is created. If the account is yours and you have no knowledge of an AccountId string, then there probably is no AccountId associated with that account and you can ignore. Please provide all of the information you are receiving into this thread. It is difficult to determine the real problem without seeing the actual messages and their context.
In tpt I am loading million records and I would like to see the status that fastload produces such as loading , Below is the part of the message by TPT.
It doesn't tell how many records sent until records are completely sent. Also, how do I get data connecter producer with multiple instance to read a single file on mainframe? Without that attribute, having multiple readers, there is always 1 instance reading the file. Any help is appreciated. Due to the nature of the parallelism of TPT, we cannot output periodic messages indicating the number of records processed, because we do not have an accurate count. User often use multiple instances of an operator to gain performance and enhance the loading task with parallel processing.
These multiple instances work in a master-slave type of configuration and the slave instances that are loading data do not communicate with the master regarding number of rows loaded until checkpoint time.
Thus, only the master would be able to report rows processed and that number would not be accurate. As for the last question about condition 8 , we are aware of the issue and we are fixing it in I've been waiting on the MultipleReader fix as well. TPT has a concept of "directory scan" which means you can place more than one file in a directory or "PDS" on the mainframe and just tell us how many reader instances you want to use, and we will read all of the files in parallel.
I think this correct, but Tom would know for sure. Programing was easy. Performance was good. Hi TonyL,I want to migrate oracle database to teradata datawarehouse.
Could you please help me on this by providing a general code for such jobs You then provide an operator for loading the data into Teradata i.
We probably have samples in there. Do we need to install Teradata parallel transporter exclusively?.. I have created the script,but not able to execute the same because TPT is not installed in my machine.. From where i can install TPT? I am not able to find the same. Teradata Parallel Transporter is not part of the Teradata Database installation package.
It's part of the Teradata Tools and Utilties installation package. It's available on the Teradata Tools and Utilities media. If you already have a FastLoad and MultiLoad license, you will be able to use TPT and its Load and Update operators and the other operators that do not require licenses without the need for a new license.
My email id id dwhraghav gmail. What version of TPT are you using? Which is better? If I have a job with 3 instances and 30 sessions as Maxsessions, you indicated that every instance will utilized 10 sessions each. In this case , if the job is not utilizing the 3rd instance at all, do the 10 sessions for the 3rd instance go waste and the job runs with 2 instances, 10 sessions each?
In most cases unless you have a very slow network between the client server and Teradata, or your Teradata system is really slow , 2 instances of the Update operator should be enough. In fact, in some cases, you would only need 1 instance, but you will have to experiment since you know your environment. Once you indicate the number of instances, that is the number that will get started up as the operators are being executed.
However, at runtime we do not know how many will be used until the data starts flowing. As long as the first instance can keep up with the rate at which data is flowing through the data streams, it will get all of the work.
If the first instance's data buffers become full, then data will be directed to the 2nd instance. Only when the 2nd instance cannot also keep up with the rate at which data flows through the data streams will data get directed to the 3rd instance. That 3rd instance will always be there with connected sessions. If the 3rd instance never gets used, then you are, in fact, wasting resources.
You would be better of with just the 2 using 15 sessions each. There if no formula to determine the number of instances because data is not fed to the instances in a round-robin fashion.
The less instances you use, the more sessions each instance can connect. The capabilities include:. Teradata Interview Questions. Below are some of the features of Parallel Transporter that can be used to increase load throughput:.
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