Skip to main content

Data Modelling issues with Split, Ragged and Recursive Hierarchies in Microstrategy

Data Modelling issues with Split, Ragged and Recursive Hierarchies in Microstrategy

 Edit 0 1…

TN6831: Known data modeling restrictions and solutions in MicroStrategy SQL Generation Engine 8.1.x and 9.x

https://success.microstrategy.com/t5/Architect/TN6831-Known-data-modeling-restrictions-and-solutions-in/ta-p/167845

I. Split Hierarchy with M-M relationships:

ExplanationA split hierarchy is the one - that at the lowest level - has more than one child. The schema looks like the following diagram.
TN5200-7X0-0123A.gif
TN5200-7X0-0123A.gif
ProblemReports that contain or will ignore filters on
RecommendationMicroStrategy recommends to have only one child at the lowest level.
Workaround / SolutionMake B and C IDs to be compound with A


II. In-line M-M Relationships:


ExplanationAn in-line many-to-many relationship involves an attribute with at least one parent and one child . Its relationships with them are many-to-many.
TN5200-7X0-0123B.gif
TN5200-7X0-0123B.gif
ProblemDouble counting, ignored filters.
RecommendationMicroStrategy does not recommend this type of schema.
Workaround / SolutionModify table structures, remove M-M relationship.



III. Star Schemas:


ExplanationThis schema is characterized by one lookup table per dimension, with base tables at the lowest level. This is the fastest way to set up a data warehouse:
TN5200-7X0-0123H.gif
TN5200-7X0-0123H.gif

This type of schemas is fully supported but difficulties may arise when adding aggregate tables:
TN5200-7X0-0123I.gif
TN5200-7X0-0123I.gif
ProblemDouble counting. According to the diagram above, a report that contains and the a metric SUM(SALES_AMT) will go to the aggregate table and join to the column to retrieve the description from the table. Since the column is not unique in its lookup table, the results will appear duplicated.
RecommendationMicroStrategy engine is optimized to work with snowflake schemas, where each attribute level has a distinct lookup table. Star schemas are supported, as long as fact tables are not at a higher level than the dimension tables to which they are joined. Consult the following MicroStrategy Knowledgebase document for further information.
TN19194 - Considerations for the use of star schemas with MicroStrategy SQL Generation Engine 8.1.x and 9.x
Workaround / SolutionIf aggregate tables are needed, use one lookup table per attribute to avoid double counting.



IV. Recursive Hierarchies:


ExplanationA recursive hierarchy or recursive dimension, usually consists of elements that point to other elements pertaining to the same attribute with a parent-child relationship. A classic example is an organization chart:
TN5200-7X0-0123J.gif
TN5200-7X0-0123J.gif

This information can be stored in a recursive fashion in only one table:
TN5200-7X0-0123K.gif
TN5200-7X0-0123K.gif
ProblemRecursive hierarchies are not natively supported by MicroStrategy 8.x
RecommendationExplode the schema from recursive to dimensional
Workaround / SolutionThe recursive hierarchy table has to be split into several tables, one for each level in the hierarchy. A physical snapshot of the solution is:
external image TN5200-7X0-0123_19.gif
Each attribute has a 1-M relationship with its child.
V. Ragged Hierarchies
ExplanationA ragged hierarchy is the one in which the parent attribute element of one or more
attribute elements are not in the level immediately above the attribute. In short, some attribute elements
don't have a relationship with their parent attribute, but instead have a direct
relationship with a grand-parent. Information in a ragged hierarchy may look like:
external image TN5200-7X0-0123_14.gif
Notice that the Esprit and the Diablo have a missing entry for the Branch, but they have one for the corporation.
ProblemRagged hierarchies are not natively supported by
MicroStrategy 8.x
RecommendationCreate entries for the missing attributes.
Workaround / SolutionConsider the case where the data has the following format:
external image TN5200-7X0-0123_15.gif
external image TN5200-7X0-0123_16.gif
New entries for the missing attributes should be added to the Branch attribute lookup table. These entries have to keep the one-to-many relationship of the attributes, so they can not share the same ID. As shown below for the above example, the entries should be added to the LU_BRANCH table. Additionally the BRANCH_ID column of the LU_MODEL table must also be updated:
external image TN5200-7X0-0123_17.gif
external image TN5200-7X0-0123_18.gif

Comments

  1. Aaron jhonsonApril 19, 2022 at 5:27 AM

    I truly appreciate the time and work you put into sharing your knowledge. I found this topic to be quite effective and beneficial to me. Thank you very much for sharing. Continue to blog.

    Data Engineering Services 

    AI & ML Solutions

    Data Analytics Services

    Data Modernization Services

    ReplyDelete

Post a Comment

Popular posts from this blog

Microstrategy "Error type: Odbc error. Odbc operation attempted

 "Error type: Odbc error. Odbc operation attempted: SQLExecDirect. [HYT00:0: on SQLHANDLE] [MicroStrategy][ODBC Oracle Wire Protocol driver]Timeout expired" is shown when executing reports from Web When users are trying to execute some reports in MicroStrategy web in particular, they may receive the Error “SQL Generation Complete Index out of range” and “Timeout expired” error as shown below: Possible Causes: One possible cause is that the MicroStrategy Intelligence Server using a cached database connection that was already dropped by the RDBMS. To resolve this: Admin should delete the database connection caches and create a new DSNs in case they are sharing DSNs to connect to different databases. In addition, change the settings for the ‘Connection lifetime’ and the ‘Connection idle time out’.  Follow the steps below to perform the mentioned changes and verify the report after each step and some of the settings require i-server r...
4 comments
Read more

Execute Integrity manager test from Command line

Execute Integrity manager test from Command line  MSTR Integrity Manager allows the user to execute a test without having to load the GUI, or to schedule a test to run later at specific times or dates. Go over using Windows AT command at: https://support.microsoft.com/en-us/help/313565/how-to-use-the-at-command-to-schedule-tasks https://www.lifewire.com/at-command-2618090 Here are the prerequisites to execute a test from the command line: Create a test and saved using the Integrity Manager graphical interface. Make sure that the users has the ' Use Integrity Manager ' privilege for that project(provided by the administrator) and the ' Execute ' permission for the reports to be tested. Keep in mind that MicroStrategy Integrity Manager can only test three-tier projects, i.e., projects which are connected to a MicroStrategy i- Server. Projects in Direct Connection (two-tier) mode cannot be tested with this tool...
1 comment
Read more

Scheduling a report or document to be sent to an FTP in MSTR

Scheduling a report or document to be sent to an FTP server You can have a report or document automatically delivered to a location on your FTP server on a specific schedule. To do so, you must subscribe to the report or document, as described in the steps below. You can customize your subscription by typing macros in the  File Name ,  Sub-folder , or  Zip File Name  fields. These macros are automatically replaced with the appropriate text when the report or document is delivered. For example, you create a subscription to a document. If you type  {&Project}  in the  File Name field, the name of the project in which the document is saved is displayed in the name of the document when it is delivered. • This procedure assumes that an administrator has already added your FTP server as a new device in Developer. Steps to do so are included in the  System Administrator Help . To send a report or document to an FTP server on a schedule ...
Post a Comment
Read more

Types of prompts in Microstrategy

Types of prompts in Microstrategy The different types of prompts allow you to create a  prompt  for nearly every part of a report. Prompts can be used in many objects including reports, filters, metrics, and custom groups, but all prompts require user interaction when the report is executed. The correct prompt type to create depends on what report objects you want users to be able to base a filter on to filter data, as described in the list below. Filter definition prompts   allow users to determine how the report's data is filtered, based on one of the following objects: Attributes in a hierarchy : Users can select prompt answers from one or more attribute elements from one or more attributes. The attribute elements that they select are used to filter data displayed on the report. This prompt lets you give users the largest number of attribute elements to choose from when they answer the prompt to define their filtering criteria. For example, on a repor...
1 comment
Read more

Types of result caches in Microstrategy

Types of result caches Microstrategy The following types of  result caches are created by Intelligence Server: • Matching caches • History caches • Matching-History caches • XML caches All document caches are Matching caches; documents do not generate History caches or XML caches. Intelligent Cube reports do not create Matching caches. Matching caches Matching caches  are the  results of reports and documents that are retained for later use by the same requests later on. In general, Matching caches are the type of result caches that are used most often by Intelligence Server. When result caching is enabled, Intelligence Server determines for each request whether it can be served by an already existing Matching cache. If there is no match, it then runs the report or document on the database and creates a new Matching cache that can be reused if the same request is submitted again. This caching process is managed by the system administrator and ...
Post a Comment
Read more

Custom Subtotal Displays in MicroStrategy

Defining custom subtotal displays in MicroStrategy By default, when users apply subtotals in a report, the name of the subtotal is displayed in the subtotal line items that appear in the report. Users can use custom subtotals to give more control over the characteristics of a subtotal. Custom subtotals allow users to define custom subtotal line items that appear on the reports  U sers can make the subtotal name dynamic by typing special characters in the subtotal name field as listed in the following table. Character Description #A The name of the attribute under which the subtotal appears. #P The name of the attribute to the left of, or above the attribute under which the subtotal appears. #0 All the forms of the parent element. #1 The first form of the parent element reading from left to right or from top to bottom. #2 The second form of the parent element reading from left to right or from top to bottom. #3 The third form of th...
Post a Comment
Read more

Level metrics in Microstartegy/MSTR

Level Metrics Level metrics allows the users to choose the right combination of level target, filtering, and grouping (referred to as elements) to achieve your desired results.  The elements of a metric level are described below: • Target : The target is the attribute level at which the metric calculation groups. For a more detailed description, see  Target: The context of a calculation . • Grouping : Grouping determines how the metric aggregates. For a more detailed description, see  Grouping: How aggregation is performed . • Filtering : Filtering governs how the report filter interacts with the metric calculation. For a more detailed description, see  Filtering: Interaction with report filters . The level is indicated between the curly braces ({ }) in the metric definition shown below: Sum(Revenue) {~, Product} The tilde (~) represents the report level with standard filtering, denoted by the plus sign (+). If you add item as a level, th...
Post a Comment
Read more

Super Cubes in MicroStrategy 2019

Super Cubes in MicroStrategy 2019 Beginning in MicroStrategy 11.0 and 2019, users will notice objects referred to as " Super Cubes ".  Super Cubes are simply a renaming of what was previously referred to as MTDI (Multi Table Data Import) Cubes. Note that only the naming convention has changed, as the functionality remains the same . This name change is visible in MicroStrategy Workstation and MicroStrategy Web. In MicroStrategy Workstation, right click on any cube created via Data Import and select Properties . The object Type is listed as Super Cube: This can also be seen when editing or authoring a dossier. In your Datasets panel, hover over the name of your dataset. The tooltip will show the dataset type listed as a Super Cube.
Post a Comment
Read more

"System Prompt" and its uses in MicroStrategy

System Prompt and its uses in MicroStrategy WHAT IS A "SYSTEM PROMPT"? "System Prompt" is a system object that was introduced back in version 8.0.0. The object is named as "User Login" and is implemented as a prompt object. The object can be found under Public Objects > Prompts > System prompts, as shown below: Unlike ordinary prompt objects, system prompts don't require any answers from the user. When a report containing a system prompt runs, the prompt is answered automatically with the login of the user who runs the report. On the other hand, like other prompt objects, answers to system prompts are used to match caches. Therefore, users don't share caches for reports that contain system prompts. For details on how caches are matched, refer to the following MicroStrategy Knowledge Base document: KB5300-7X0-0147 - How are caches matched in MicroStrategy Intelligence Server 7.x? WHEN ARE SYSTEM PROMPTS USED?    System pr...
Post a Comment
Read more

Microstrategy Caches explained

Microstrategy Caches Improving Response Time: Caching A  cache is a result set that is stored on a system to improve response time in future requests.  With caching, users can retrieve results from Intelligence Server rather than re-executing queries against a database. To delete all object caches for a project 1 In Developer, log into a project. You must log in with a user account that has administrative privileges. 2 From the  Administration  menu, point to  Projects , and then select  Project Configuration . The Project Configuration Editor opens. 3 Expand  Caching , expand  Auxiliary Caches , then select  Objects . To delete all configuration object caches for a server 1 Log in to the project source. 2 From the  Administration  menu in Developer, point to  Server , and then select  Purge Server Object Caches . 4 Click  Purge Now . To purge web cache follow the steps in the link ...
3 comments
Read more