The horizontal axis represents the internal table partition associated with a certain week (week date range manually added for readability). What tables/cylinders are currently in TIM Cache?įigure 1 illustrates the simulation of a retail application that queries sales numbers against current day against day last week, last month, and day last quarter. How do I verify if the table is actually in the TIM Cache? I just loaded a table with QUERY_BAND with TVSTEMPERATURE=VERYHOT. What perm data is staying in the HOT area for more than a week but never made into the VH range?ĭid my VeryHot loaded partition cool down below VeryHot or Hot yet? What tables/partitions cooled down from TIM cache target temperature last night? How quickly did my month end tables cool down below the HOT range?įor my largest table – how quickly does the temperature of the non-recently-loaded partition (week a month ago and week a year ago) heat up and what temperature did they get? What tables were in the VeryHot temperature range last Tuesday? Here is the list of some questions the heatmap data is intended to address: The history data will enable the users to analyze the temperature change of the data at a cylinder level on a given time period very quickly. Data temperature values are maintained by the TVS allocator vproc.Īlthough a current snapshot of the heatmap report can help the users answer some of temperature related questions about their tables, heatmap data that has been captured over time will provide even greater value to administrators. If a cylinder stops being accessed then its temperature will start to drop, and over time it may fall to zero. The cylinder temperature decreases over time through the use of a mathematical model. The cylinder temperature increases as data access on that cylinder increases.
Specifically, TVS monitors customer data block reads and writes, and full cylinder reads. TVS Metric Collection monitors how often data is accessed by the database on a per cylinder basis. See Appendix A for ‘How to check to see if TBBLC or TVS is enabled’. The system is enabled with Teradata Virtual Storage(TVS) – ONE_DIMENSIONAL with Metric Collection On The system is enabled with Temperature Based Block Level Compression (TBBLC) The data temperature collection requirements are described as follows: The users can run the heatmap function with or without TIM enabled on their system as long as the data temperature collection requirements are met. Then we will click OK.The heatmap table function requires Teradata 14.10 (or higher) and the system that must have data temperature collection enabled. Here we will set the Variable Name as JAVA_HOME and the Variable Value the path or Java, JRE or JDK which is C:\Program Files\Java\jdk-12 in this example. We click to the New in order to create a new system variable. Open Environment Variablesīelow we can see the environment variables menu where we will create the JAVA_HOME system variable and set the path accordingly.
In the system properties, we will navigate to the Advanced tab which provides the Environment Variables button like below. We can also open it from the File Explorer -> Computer -> Right Click. We will open the computer properties with by running sysdm.cpl in the Run menu like below. We can set this path as Java HOME_PATH environment variable. Now we have learned the path of the Java, JRE or JDK installation. Locate JRE or JDK Path Set Java HOME_PATH Environment Variable Locate JRE or JDK PathĪnd under the Java directory the JDK is residing. JRE or JDK generally installed on the Program Files or Program Files(x86) directory under the Java directory like below.
Locate JRE or JDK Pathīefore starting the configuration we have to locate the JRE or JDK path.
In this tutorial, we will learn how to set up Java, JRE, and JDK operating system path variables in order to work properly. JDK or Java Development Kit is used to develop Java applications. JRE or Java Runtime Environment is used to run Java application. Java is a very popular programming language which provides a different component in order to run, develop Java applications.