That said, you can refresh this extract on a regular basis using Tableau Prep Conductor. Data blending will allow you to link the 2 tables together but when you try to bring data from the secondary source to the primary it will come across as an aggregate at the level of the link - and it will limit the functionality available to you in Tableau - can't filter across the blended data sets , no LODs using the secondary source to name a fesUsing a data source that has multiple, related tables affects how analysis works in Tableau. (2) Yes. Data blending in Tableau enables the integration of data from different sources or tables without the need for traditional database joins. With data blending, the linking field from the primary data source must be in the view before you can use a Level Of Detail expression from the secondary data source. 2, Tableau is about to release a quite revolutionary feature that will change the way we set up our data sources. Tableau Data ManagementOne example of how Tableau changes behavior based on what the driver reports is the list of functions available when creating a calculated field. A data model can be simple, such as a single table. Data connectivity: Allows easy connect to and data blending across a wide range of sources, including spreadsheets, databases, cloud services, and big data platforms. Introduction to Data Blending in Tableau This article covers how ️ Data Blending works, types & limitations Get step-by-step guidance. To do so, right-click on the "sales per customer" pill. Tableau isn’t the foremost expensive visual image package, particularly compared to such business intelligence giants as Oracle’s and IBM’s solutions. In some cases Tableau will require you to create a data extract from the data returned by the ODBC connector. Relationships have fewer technical limitations than data blending and are the recommended way of combining data when possible. Environment Tableau Desktop Answer Assess your data and consider the following: How many connections you have in your workbook Edited by Tableau Community June 30, 2020 at 7:16 AM Hi, Pavan other than the normal issues listed in below link, I don't think there would be limitation to create workbook based on 6 data sources blended. ×Sorry to interrupt. The limitations of data blending in Data Studio. All identical, the license is sort of expensive for many little to medium corporations. 2) or Not ,one point we need clarity on is below . For more details on these areas and many more, check out our whitepaper on designing efficient workbooks. Thanks, PaoloDashboarding tools like Tableau, Looker Studio, and Power BI are great for data visualization and offer some transformation capability via inbuilt functions. Tableau platform is known for its data visualization functionality. The data appears as if from one source. Tableau Desktop allows you do to very basic preprocessing. 2. Joining 2 tableau data sources (extracts) doesn’t allow accurate rolled-up/total calculations when a measure is coming from each source. Data blending provides a way to combine data from more than one data source on a single worksheet. Click on the average option in the drop-down. Tableau Data Blending Limitations: A Closer Look. Limitations of Data Blending in Tableau. When blending data, you merge data from a secondary data source and display it alongside data from a primary data source in a view (i. Any limit, both physical and theoretical, is determined by a large number of factors including, but not limited to, the following: Hardware resources, such as RAM, CPU, and disk space. Tableau has to take a copy of the data and paste it if you would in a different format and language entirely, a . Data blending is not a database join engine, but an in-memory method for visualizing data from different data sources. In Tableau, in order to get around that problem, we blend the data from the BW query with a MySQL table, containing the permissions. Blend using COUNTD (Red tab) I know this is a limitation in tableau as I'm unable to switch from SUM (Case Number) to CNTD (Case Number). Limitations of Data Blending in Tableau: The following is a list of a few restrictions on using Data Merge in Tableau. Tableau's Context Filter is the first filter to be applied to a worksheet after any other filters. If there is a worksheet that has all of the additional filters to create the desired relevant values, then add the filter from that worksheet. There are some data blending limitations around non-additive aggregates, such as COUNTD, MEDIAN, and. . Portent’s Michael Wiegand has written about data blending in Google Data Studio multiple times. When we work with large amount of data, multiple data sources, dashboards and workbooks, which heavy loaded with individual views and elements to control those. Now I want to calculate similar type of total percetange based on a dimension. Expand Post. What are some basic limitations of data blending in tableau? Limitations of Data Blending in Tableau. The content in this topic applies to all platforms, unless specifically noted. Blending data from two data sources and EXCLUDE Hello, I am working with two Data Bases that are essentially the same, but I use the second one to "fake" dates (basically the same date +1 year) in order to use it for the YoY comparison that aligns with the different filters I set. Blending will "blend" them together into a single element. Get Trained And Certified Over 2. Alternative to CountD function in Blending. LOD from the secondary datasource; Blended data sources cannot be published as a unit. Use a blend when: You want to combine measures or dimensions with the same meaning but different names in each table. Because Tableau handles combining the data after it is aggregated, there is less to combine. Create visualizations for your data. Loading. Drag a table to the canvas (if needed), then on the Data Source page, in the left pane, select the Use Data Interpreter check box to see if. Tableau has an ability to blend data. Blends may contain more rows than the original data. I generally recommend cross-database joins because they avoid the many limitations of data blending. The blended data can’t be published to Tableau Online or Tableau Server. I hope I understood you correctly: You have two databases (SAP EEC and BW) and each sits on its own local hyper files, call it SAP-Hyp and BW-Hyp, created by Alteryx. Some of these limitations are: Tableau does not. Also, can anyone tell me what is the best practice in Tableau when trying to data blend manually adjusted Data. But these kinds of tools are unable to perform advanced data manipulations. I've attached the packaged workbook. Blends can also be limited in the types. Resolution. I am using Tableau 8. there is only one record for each value in the linking fields in each table). If the secondary table has a large amount of data then data blending may be faster, because data blending will aggregate the data first. Best-of-breed data preparation platforms such as Datawatch Monarch, Alteryx, Vero Analytics etc. A default blend is equivalent to a left outer join. There are actually quite a few sources but the gist is that it doesn't seem to work like this when blending in Tableau. Meaning, if you have one primary data source selected and you have another on the server, you can bring data from both sources into one worksheet. Tableau Data Blending Limitations: A Closer Look. Good morning. The Tableau’s extract may be updated daily, weekly, or monthly during off-peak hours. Make your data more discoverable by categorizing it within Tableau. Ability to use different types of join (left join, right join, inner join and full outer join) Uses only left join. Limitations of Data Blending. Conclusion. Used when the dataset is from a different data source. The latest version of Tableau, 2020. ×Sorry to interrupt. Upvote. Data Blending. Blending from a polygon-based map to an existing data source which uses 1-to-many joins. I am using blending and created Relationship but i am having problem in terms of getting distinct count from one of the data sources. This means that if you have a field with two values 0 and 1 in a table with 100 rows, this function will return the value 2, unlike COUNT. When we do this using Tableau’s data blending – the steps that are happening are (see the Tableau video to see HOW to do this): 1. For example, you could manually map a user named “Alice” to the value “East” so that she only sees rows in the data source where the “Region” column is. Calculated field does not appear in the Field drop-down list of the Sort dialog box when the calculated field uses data blending; Tableau Data Blending Limitations & Rules. Occasionally when working in Tableau, thee want have to perform a functionality called intelligence mixing, which involves combining data from different sources. Ignite Your Potential- Upto 30% Off + 20% Cashback Course Free | OFFER ENDING IN : Enroll Now! All Courses . blends joins new data model noodle relationships Tableau Tableau 2020. Go through the link for more details. A data model can be simple, such as a single table. You need to publish each data source and then blend the published data source. to ascertain the data and acquire a transparent opinion supported the data analysis. A data source with relationships acts like a custom data source. Many Tableau developers find data blending frustrating. For example, you can aggregate data on the year rather than the date, or on the product type instead of the product name. Occasionally when working in Image, you will have at perform a function called details blending, which concerns combining data from different sources. A simple example is having (a) a data source with three columns including location names and latitude/longitude values, and (b) a data source with location names and detailed information about each. With that, you will now head to the next type of LOD Expressions in Tableau, which is the EXCLUDE LOD Expressions in Tableau. 5%. This will greatly enhance Tableau's efficiency, particularly when there are several filters set to the worksheet. I'd like to add a count distinct of a varchar from the secondary data source to the measure values shelf. Any other data source you use will be a secondary data source. Option 3: Add the memory of Tableau Server machine. Also if the refresh time of a TDE is more than the. mdb, which is an. Tableau Data blending compromises on the speed of query in high granularity;The Two Types of Self-Service Data Preparation Tools. In this source create a calculated field to pull out the KMs on the date of oil change. The main disadvantage of using Tableau is, only recent versions supports revision history and for the older one's package rolling back is not possible. In the calculation dialog box, do the following: In the name text box, enter Sales for Store - South. 1st Oct, 2022 Views 0 Read Time 6 Mins In this article 1. You define relationships based on matching fields, so that during analysis, Tableau brings in the right data from the right tables at the right aggregation—handling level of detail for you. 1. as we all know that there are some limitations when we try to build a view from 2 different data sources especially global filter issues. Hi All, We are in a phase to decide whether to buy Tableau Server(9. Next, create a table calc using the [Start KM] to calculate the total KMs:2) You can have a total of more than 2 data sources in your view that are blended, but only ONE data source can ever be the Primary data source in a specific sheet. Establish a relationship at the level needed to blend and not at the duplicating field level: Data > Edit Relationships. In my experience a 4GB machine will choke on a chart will a couple of million points (e. However, data cleansing is a necessary step. Cube data sources are used as primary data sources for data integration in Tableau and cannot be used as secondary data sources. Data blending is a very useful tool, but there are some effects on performance and functionality. So you wouldn't be able to compare the dates from rows of Something and the dates of rows from Dim_Date. Limitations of Data Blending in Tableau. Understand the limitations of data blending in Google Data Studio and learn the tips to get past those limitations. Let say from DS1 if i am making it as primary datasource then i can get the. e. You can use data blending when you have data in separate data sources that you want to analyze together on a single sheet. Tableau is strictly a visualization tool. So far, so good. is there a limitation to oracle db? ThanksI data blend on Date. July 12, 2020 Tableau Desktop is one of the most common tools used by analysts. From the Data pane, under Measures shelf, drag the field Sales Per Customer from the Rows shelf and drop it on the left of field SUM (Sales). Choose the table (s) that should be secured by this policy. Blend on Summary Data. Connect your data to your account. Data blends are a special kind of left join that only occurs after the data has been returned from your two datasources. There are few limitations of Tableau data blending around non-additive aggregates like RAWSQLAGG and MEDIAN. Step1: Load Dataset into the Tableau. Or it can be more complex, with multiple tables that use different. Occasionally when working in Tableau, you will have to perform a function named data blending, which involvement combining data from different sources. At first, try a simple join. Instead, the values have to be calculated individually. Hope this helpsBlending will limit the functionality available to you in Tableau - cant us LOD - no filtering across the data sources - the data from the secondary source are aggregated at the level of the link . Data Blending — Tableau recommends blending data on low-granularity dimensions. lt is offering more than 3500 data points for drilling down the dataset. After bringing out the first table of data, click the Add link to the right of the Connections heading in the Left pane. JSON file data source example. Data blending is an method for connect data from multiple sources. The following are the constraints that apply for LOD expressions. In the paper, Kristi talks about why Tableau’s Data Blending has taken us closer to that scenario: “Because our data blending is workload-driven, we are able to bypass many of the pain points and uncertainty in creating mediated schemas and schema-mappings in current pay-as-you-go integration systems. . Data blending has several limitations that makes it difficult to. When we work with large amount of data, multiple data sources, dashboards and workbooks, which heavy loaded with individual views and elements to control those. Step 2: Now add these data sources in Tableau. while data blending is a great feature for exploratory analytics and data validation and incredibly useful to have as an extra tool when nothing else will meet the requirements I find that there's a tradeoff with added. g. When two data sets are blended together there is an increase in time to. Although Data Blending in Tableau can be a vital asset to your organization, it has a few limitations. Click on Data 🡪 New Data Source, Select the second data connector and connect to the second set of data. Switch between data connections in the Left pane, then drag out the desired table to the canvas and release it. When it comes to combining our data within Tableau, we have three options. Despite the advantages of data blending, it also has some downsides, as shown below: Data blending works with the left join under the hood, and it does not perform any other types of joins. Soporte prémium; Aprendizaje y certificaciones;Step 3: Use the LOD expression in the visualization. This creates a Left Join as you mentioned previously. You're seeing an asterisk because of it. This is useful for analyzing related data from multiple sources in a single view. When two data sets are blended together there is an increase in time to query and render due to an extra step that is being taken in the queries. there is only one record for each value in the linking fields in each table). 1 brings new capabilities to help save you money and time—including Accelerator Data Mapping, Tableau for Slack enhancements, Identity Pools, and more. Data blending: Cube data sources can only be used as the primary data source for blending data in Tableau. A datetime field in the primary data source, for example, will not blend with a date field in the secondary data source. For more information, see Troubleshoot Data Blending; Blended data sources cannot be published as a unit. Tableau has to take a copy of the data and paste it if you would in a different format and language entirely, a . Drag out a second table. It is a model data set of what I am trying to achieve. Because Tableau handles combining the data after it is aggregated, there is less to combine. If we publish Excel Data source, SQL server data source and SAP NetWeaver Business warehouse data source to the Tableau server . Click on the average option in the drop-down. Example 2 is a special case the the more generic blending problem. For help with potential issues, please see Troubleshoot Data BlendingThe introduction of Tableau Prep provides a slightly more flexible and automated way to prepare your data – blend and transform – for analytics in Tableau. Loading. 1, you can now create and edit flows in Tableau Server and Tableau Cloud. That’s because they aren’t supported for cross-database joins yet. Data blending is particularly useful when the blend relationship. The disadvantage of blending will be its limitations in this case as I mentioned above: Limitations around non-additive aggregates, COUNTD, MEDIAN, and RAWSQLAGG. Photo by fabio on Unsplash. There are two ways to combine data in Tableau: data joining and data blending. However, the resulting data can be de-duplicated using calculations. If you are experiencing that issue, I recommend opening a support case so that we can investigate it. Data blending brings in additional information from a secondary data source and displays it with data from the primary data source directly in the view. will it be possible for us to blend the SAP BW data source and SQL data source from the Tableau server to. tde. Occasionally when working in Tableau, you will have to perform a function called data blending, which involves combining data from different sources. Data preparation and blending features are found in two types of self-service tools: Visual analytics platforms such as Tableau, Qlik Sense, Spotfire etc. We joined (inner join) two data tables with join keys (Month, Type, and Color). The underlying data source. Data blending limitations. They cannot be used as secondary data sources. Visual analytics tools are basically. Relationships defer joins to the time and context of analysis. However, there are instances where data blending does not perform effectively and data from different sources are brought into. Data Blending Feature in Tableau. Hi Logan, Matthew has already provided good guidance, but I wanted to point out another technique you may find useful for data blending. All Courses ;Option 1. Be aware of the level on which you are blending (you want to blend on as high a level as possible) and also the amount of data. Although they do offer data blending functionality, in practice, it's rather difficult to set up and debug. Below mentioned are the areas where Data blending is used. Data Blending Limitations with COUNTD, MEDIAN, and RAWSQLAGG | Tableau Software. I have 2 published datasource and i think i cannot perform JOIN, LOD and COUNTD. From the Connect pane, connect to an Excel spreadsheet or other connector that supports Data Interpreter such as Text (. Often if an extract is not performing very well it has to do with your harddrive needing to be defragged or you have too many calculations, badly set. AVG is a quasi-additive aggregation and may not be supported when blending. His articles have showcased the potential promise—and limitations—of data blending. If so, then there are over 30 different listed data source connection types in Tableau Pro however this is a bit confusing because some of these connection types are things such as "ODBC" or "OData" which could include other data base types while relying on connection specific definitions configured by the end user. Fast to create interactive visualizations. but using our SQL Server data, Tableau. If the secondary data source has LOD (have different granularity), they are taken down after data blending. See Join Your Data - Tableau The only issue with joins is potentially duplicate data (which can be fixed, see Removing Duplicate Data with LOD Calculations) and after that you're golden. This behavior appears as if the blend is acting as an INNER ad-hoc join rather than a LEFT ad-hoc join. Identity Pool will enable you to branch out of the strict single identity store limitation we have in Tableau Server. Tables that you drag to the logical layer use. One limitation of blends is that they can be slower than joins or relationships because they require Tableau to actually create that temporary table to blend the data. A blend merges the data from two sources into a single view. can I make dashboard with 6 different source by using data blending option in tableau?. Data blending does not work with certain aggregation levels, such as MEDIAN and COUNTD (count distinct). 1 is here with new capabilities to increase productivity and save time and money. There are 3 different ways to merge data together from different data sources, Data Relationships, Data Joins and Blends. Let us have a quick review of the limitations of data blending in the tableau platform. The Dataslayer add-on is a reporting tool for your online PPC/SEM marketing. Because of this, my percent calculation (Calculation1) does not work either. Option 1: Add the filter from a different worksheet. Data blending has some limitations regarding non-additive aggregates such as COUNTD, MEDIAN, and RAWSQLAGG. Starting in Tableau version 2020. The actual data set I use is huge and a join is too slow. No Automatic Refreshing of Reports:Back on the data tab, click the “add” link to add other connections to this data source. Connect to a set of data and set up the data source on the data source page. For details, see Troubleshoot Data Blending. With that, you will now head to the next type of LOD Expressions in Tableau, which is the EXCLUDE LOD Expressions in Tableau. Blend published data sources. For more information, see Troubleshoot Data Blending Relationships defer joins to the time and context of analysis. The data source with the KMs is the primary source. The first field you drop onto a worksheet defines the primary datasource. Hi @Kathryn Campbell (Member) -. Although they do offer data blending functionality, in practice, it's rather difficult to set up and debug. I’ll provide some. Select the "Measure" option. Instead, publish each data source separately. Step 1: Add the first dataset as shown below. at a high a level in the data as possible. It appears that Window calculations are the answer. 7 MB of data is expected to attain. Limitations Data blending is the equivalent of a left outer join, sort of. Tableau Data Blending Limitations. The Two Types of Self-Service Data Preparation Tools. ×Sorry to interrupt. ” In other words, Data Blending. tde. Data preparation and blending features are found in two types of self-service tools: Visual analytics platforms such as Tableau, Qlik Sense, Spotfire etc. Date. Aggregate, join, or union your data to group or combine data for analysis. Everyone tells blend it is for different data sources but I can see even cross join can be used to join different data sources. Tableau Performance Optimization. Users may need to invest in additional tools. Prototyping how data should be modeled and brought into a data warehouse in order to meet report and visualization needs. Step 1: Connect to your data and set up the data sources. Data aggregation jeopardises the speed of query performance with high granularity. Blending tips. However most extracts can be queries in seconds even when they are very large. For example, select Analysis > Create Calculated Field, and in the Formula text box, type the. This is the new data blending introduced in Tableau v8 that lets have secondary dimension filters and blend on dimensions that aren't in the view. They cannot be used as secondary data sources. The following are the limitations of LOD expressions:. In tableau I would just do data blending with date and the graph will have the data from both tables grouped by date. Blend using AVG (Green tab)You can think of a data model as a diagram that tells Tableau how it should query data in the connected database tables. 3. Admins can now define custom data labels that Creators and Explorers can add to data assets. Cause. A major use case for data blending is within data pipelines that feed downstream analytics. Loading. Blending Data Via Multi-Dimensional Scaffolding . any enhancements on data blending in Tableau. This guide to Tableau data blending covers: Tableau data blend vs a join Data blending best practice How to blend data in Tableau Limitations. I am trying to 'blend' the two published data sources (instead of joining them as they are at different grain and join will not be a good solution and will create lots of dup records). See Fill Gaps in Sequential Data for directions; Notes on Option 4 (data blending): Data blending has many limitations. Using relationships, we can do this in one datasource. You’ll notice that a number of the connection types are grayed out. tableau. Joins, Relationships, and Blends. Learn to analyze and visualize data in Tableau through real-life datasets in Tableau 2022 A-Z: Hands-On Tableau Training for Data Science. Join Your Data - Tableau (directions on how to do a cross-database join) Removing Duplicate Data with LOD Calculations . You can see aggregations at the level of detail of the fields in your viz. Meaning, if you have one primary data source selected and you have another on the server, you can bring data from both sources into one worksheet. Prototyping how data should be modeled and brought into a data warehouse in order to meet report and visualization needs. Step 1: Connect to your data and set up the data. 2. There are a few workarounds:. In order to create a join between data tables, we need to open the data source tab inA data policy is applied and filters the data when it's viewed in the Tableau content (for example, a workbook or flow). Click Extract. Limitations Data blending is the equivalent of a left outer join, sort of. You cannot publish the blended data sources on Tableau Server directly. Dashboarding tools like Tableau, Looker Studio, and Power BI are great for. Along with the table names, we can see the contents or fields contained in each table from the data pane. Tableau will then select a primary key to blend the data together. This allows businesses to avoid using third party tools and applications to connect and source data from various enterprise systems. Starting in Tableau version 2020. Limitations of data blending in Tableau: Every tool, feature, or platform will have its limitations, which would be the future enhancements. For more information, see Alias Field Values Using Data Blending. When there is lesser data to combine, generally, performance improves. To populate your Tableau Cloud site with content (data, reports, and so on), you or the data professionals in your organization publish that. csv) files, PDF files or Google sheets. A better approach is to aggregate the tables, then blend the data on the aggregate. I have investigated and found it is tableau limitation as per my knowledge. Instead, publish each data source separately (to the same server) and then blend the published data. Tableau has two inbuilt data sources named Sample-superstore and Sample coffee chain. Data blending is particularly useful when the blend relationship—the linking fields—need to vary on a sheet-by-sheet. The limitations of data blending largely lie with the ETL solution you choose. COUNTD () – This function will always return the number of UNIQUE values in the selected field. Being able to efficiently collect and combine those data has become an essential skill for all Data Scientists…Occasionally when working in Tableau, you will have to perform a function called data blending, which involves compounding data from different sources. I believe this is not a problem because of the primary data source using Relationships but because data blending has some limitations regarding non-additive aggregates. You will make a remarkable impact and get the most valuable insights from your data sources. Methods of Combining Data: Overview . Tableau Desktop and Tableau Server do not have any enforced row or column limits for the amount of data that can be imported. Data Blending is a very powerful feature in Tableau. While it’s possible to aggregate the 1-to-many data source in the custom SQL, this can be time consuming and will require more edits when data sources change. 4. If you are experiencing that issue, I recommend opening a support case so that we can investigate it. Blended data cannot be published as a unit so the data must be published separately. Limitations of Data Blending. Creation and publication of data sources. Tableau has an ability to blend data. Apologies for the delayed reply. Quickly Create Interactive Visualization:- Users can create a very interactive visual by using drag n drop functionalities of Tableau. Tableau Desktop cannot join published data sources, most extract-only data sources, or cube data sources. 1. Creation and publication of data sources that join data across. Let’s take a look at the feature highlights for this release. The book details the role that Tableau Prep Builder and Tableau Desktop each play in data modeling. Nowadays, companies use data from different sources to solve their business problems. I have 3 different stored procedures where I’m not able to combine these 3 stored procedures in Tableau. The disadvantage of blending will be its limitations in this case as I mentioned above: Limitations around non-additive aggregates, COUNTD, MEDIAN, and RAWSQLAGG. Tableau Public; Tableau Data Management; Tableau Server Management; Análises incorporadas; Nossas integrações; Versões mais recentes; Soluções Ativar sub-navegação. You may consider moving the data to another data source, or creating a local copy of a published data source, in order to use a cross-database join, otherwise the data must be blended. To do so, right-click on the "sales per customer" pill. Option 2. However, there are ways to constrain blends using filters and calculated filters. A connection is made to both data sources independently. But Tableau Prep has major limitations as you can see in our comparison guide of Datameer and Tableau Prep, particularly for data science datasets. Blending runs a query on each data source and joins the aggregated results of those queries. as we all know that there are some limitations when we try to build a view from 2 different data sources especially global filter issues. Creation and publication of data sources. Blending data can also result in data duplication and inconsistencies if not properly managed. When you blend the two data sources on the State field, you create a link where individual state values (in the primary data source) can have multiple segment values (in the secondary data source). Any time data blending is in action tableau will be querying multiple datasets. Limitations of Data Blending in Tableau: The following is a list of a few restrictions on using Data Merge in Tableau. e. Chris, if i create dummy data, the blending works. Despite the advantages of data blending, it also has some downsides, as shown below: Data blending works with the left join under the. This should explain why when you are using the SUM aggregation it works. Loading. You can change which data source becomes Primary from sheet to sheet. When. Limitations Of Data Blending In Tableau. In Tableau Desktop: On the Start page, under Connect, connect to a supported file type or supported database type. Blending reaggregates metrics. Blending gives a quick and simple way to bring information from multiple data sources into a view. Hey Steve, Tableau should not lose the active links for data blending when the view is published. The actual data set I use is huge and a join is too slow. The only real limit on how much Tableau can handle is how many points are displayed. Or it can be more complex, with multiple tables that use different. The amount of time that the tableau server spends performing data blends is the blending data event. Using Data Blending, you may have tried to achieve relative date filtering relative to the maximum date in the data. However, in certain scenarios, there may be reasons to use Custom SQL. Note: Starting in version 2020. A secondary data source can be used to re-alias the field values in a primary data source. 2, data sources use a data model that has two layers: a logical layer where you can relate tables, and a physical layer where tables can be joined or unioned. Key points to consider include:.