This video helps the default join bw attribute-attribute metric to metric join type and Report level in Mstr. 0, the "MCE join to get data combination" setting is being retired for any project with Data Engine Version 11 or above. This allows the FOJ to be rewritten to a different kind of join in the. 1, the inherited default value for Full Outer Join Support actually changed from No to Yes. As shown in the example above, all data for cost is aggregated together and shown for every row of a category. Prerequisite Before you can perform an outer join, you must allow outer joins to be supported. RIGHT [OUTER] JOIN without the intersection. Select SQL Data Warehouses. The MicroStrategy SQL Engine applies the designated join type to the data pulled from your data source's tables. Rows containing values for inner join metrics but not the outer join metric are dropped. The Link Attributes Dialog opens. Drag the column from the first table onto the column from the second table. In MicroStrategy 10. Set the Attribute Join Behavior to "Outer Join - Preserve Filter" 4. 29K. In an inner join, only those tuples that satisfy the matching criteria are included, while the rest are excluded. By default, MicroStrategy will use FULL OUTER JOIN when needed because in SAP HANA, queries that perform full outer joins between several tables perform better than when the Full Outer Join VLDB setting is set to No Support where the SQL Engine will generate SQL. The major JOIN types include Inner, Left Outer, Right Outer, Cross JOINS etc. •. RIGHT JOIN. Why MicroStrategy Why MicroStrategy; Customer Stories; Platform So the existence of GODWFLAG is expected as metric A and B are not independent from each other though they are all outer join metrics. A FULL OUTER JOIN returns unmatched rows from both tables as well as the overlap between them. Click Save and Close. An outer join means return all rows from one table. An outer join includes all data from every element (the union of all. Too bad!Syntax for full outer join: Note:here table1 and table2 are the name of the tables participating in joining and column_name is the column of the participating tables. If a document does not contain any primary datasets, all datasets are joined using inner joins. VLDB properties allow you to customize the SQL that MicroStrategy generates. MicroStrategy - Dynamic Attribute with join. Additionally, the COALESCE function can be included in the SQL query. Brief instructions are provided using the example below. VLDB Properties. •. ttl_weight from rep_so a, rep_so_p1 b where a. There's a reason we're at the top of the list. We specialize in MicroStrategy and are expert in producing quicker, impactful and user-friendly analytics within Data Warehousing and Business Intelligence domains. To pick up the fix, upgrade to MicroStrategy 2021 or above and enable project level setting "Data Engine Version" to 2021 or above. Go to Data > VLDB Properties. select a. This option reflects the behavior of all pre-9. Create three reports named A (with attribute A), A&B (with attribute A and B),A&C (with attribute A and C) Create a dashboard based on the three reports created in last step. 0 for databases that do not support Full Outer Joins. x. ID, SERVICE_TYPE. Click the "VLDB Properties. x. item_key. Steps are as below. An inner join is created and a line representing the join appears in the Query Builder pane, running. Make sure that this attribute is stored at the specific level in the Fact table which you. Starting in MicroStrategy 11. No PostgreSQL specific customizations were made for this feature. x-10. Database instance, report. ) From the Tools menu, select Show Advanced Settings. Controls whether tables are joined only on the common keys or on all common columns for each table. Create three attributes named A, B, C, and after them added in a report in Developer, no data returns， as showed below. This issue has been addressed in MicroStrategy 2021. MicroStrategy 2021 Update Installer provides customers with a simple and centralized solution for applying critical fixes to the MicroStrategy 2021 Platform Release. Beginning with MicroStrategy SQL Engine 9. You must have write access to the datasets you intend to link. The Project-Level Very Large Database (VLDB) Property setting, found in Joins > Preserve All Lookup Table Elements, 'Preserve lookup table elements joined to final pass result table based on template attributes with filter' is not turned on, which results in. 55K KB441377: Full Outer Join Optimization implemented in MicroStrategy 11. Notice the outer join is applied, and that in the last pass of the CSI, there is a cross join between L_Category & L_Year and then "left outer join" to the Metric result. 5. DealSizeUnit should be a metric that an attribute. If the parent report is configured, under Report Data Options > Attribute Join Type, to preserve all lookup table elements joined to the final result table, then the target report will also preserve lookup table elements. The join type places conditions on the data to be displayed in the report. Right outer join: Performs a right outer join on the columns. To learn more about how the Global Optimization levels 3 and 4 handle inner and outer joins between metrics in MicroStrategy SQL Generation Engine, the below technical note can be used as reference. After the project information is. But sub-queries have performance issues. I also created an additional dummy metric that serves the same purpose as introduction of dummy data within the data warehouse. Prefix, QuantityofLicensesInstalled, Purchased. 11, analysts can now add direct links within a dossier. CREATE TEMPORARY TABLE. xWhy MicroStrategy Why MicroStrategy; Customer Stories; PlatformNote: In MicroStrategy 11. The concept is simple. Business users move seamlessly between all five styles of BI and even combine multiple styles. A simple idea would be to modify the metric by means of dimensionality, namely, the LEFT OUTER JOIN attributes with the setting ignore add / None. A simple idea would be to modify the metric by means of dimensionality, namely, the LEFT OUTER JOIN attributes with the setting ignore add / None. M,table_b. You are not really doing a Cartesian product; you are doing an INNER JOIN. It is dynamically created when a new report is created in MicroStrategy MicroStrategy Developer 9. This can be done with a union of the IDs of the multiple intermediate tables that need to do an outer join and then using the union table to left outer join to all intermediate tables, so this approach generates more passes. 1K views 3 years ago MicroStrategy In this video I will show you why you need outer joins and how to solve this for multiple scenarios in MicroStrategy using. 4. Follow the steps below. Connection Mappings stylish Microstrategy; MSTR Checking access to data; Data Modelling issues with Split, Ragged and Recur. This technical article explains a SQL. This will return all the elements present in the lookup table even if they don't exist in the fact table. Set the visualization "Join Behavior" for "All Attributes" to "Outer Join - Preserve Filter" 7. KB310329: How to achieve attribute left outer join effect in MicroStrategy Web. Countries: This is a reference table with the. 0 SP2 supports FULL OUTER JOIN syntax between tables in the FROM clause. If the condition is moved to the outer join definition this query would produce customers without orders and customers that meet the condition on order date. Tip #1: The word ‘ OUTER ‘ is optional. Procedure: Right-click on the Project name and select Project Configuration. By default, inner joins are generated against all metrics in a report. This property only takes effect if the metric formula contains facts from different fact tables. You have to emulate it by doing both LEFT JOIN and RIGHT JOIN as follows: SELECT * FROM t1 LEFT JOIN t2 ON t1. LEFT JOIN. The MicroStrategy SQL Generation Engine does not support. This property may have two possible values: 0 for inner join and 1 for outer join. This article also provides a workaround to avoid this behavior. Using MicroStrategy Developer, log in to a project connected to an MDX cube source. A simple idea would be to modify the metric by means of dimensionality, namely, the LEFT OUTER JOIN attributes with the setting ignore add / None. You can modify the join expression in one of two ways: Simple expression: This is the default. 7. x-10. The join type for all metrics on the Report is set to "Outer". It arbitrarily matches rows from the two tables, with no duplicates. Forum: Search: FAQs: Links:. Steps to Reproduce This procedure is using the MicroStrategy Tutorial warehouse that is shipped with MicroStrategy. In the first drop-down list, select the attribute to which you are linking the. Let’s study various types of Inner Joins: Theta Join. The following document provides sample code on how to modify the metric formula join type. There's a reason we're at the top of the list. Join Type for "All Attributes" is set to "Outer Join - Preserve Filter" for the Visualization. HAVING. CAUSE This is a known issue in MicroStrategy 10. Specifically if a metric at a higher level is set to outer join while a lower level metric is set to inner join while both include an attribute the lower level metrics version of the attribute will be used to join to lookup tables despite being less. In the last pass, an outer join is performed against the OL (Outer Join to Lookup) table. Theta Join allows you to merge two tables based on the condition represented by theta. Here is the workaround to achieve the attribute left outer join on MicroStrategy Web. For information on how to display this property, see Viewing and Changing Advanced VLDB Properties. Join common key on both sides. The table now appears in bold as shown below. Make sure that the report filter override option is turned off. x:The report returns the following: Notice in the screen shot above that the Data for Project B is missing. Informally, a join stitches two tables and puts on the same row records with matching fields : INNER,. The properties are saved in different folders, as indicated in the previous list. When the metric join type is set to Outer Join and the SQL Global Optimization is set to Level 4, extra SQL passes are generated. To understand Downward Outer Join, consider the following report that contains the attribute Store and two metrics, Sales Per Store (M1). Number of Views 1. c1 = t2. 4. In this case, Promotion has a many-to-many relationship to both Item and Quarter. There's a reason we're at the top of the list. If you write your queries with just ‘ FULL JOIN ‘, SQL Server knows you want to do a FULL OUTER JOIN. An inner join is created and a line representing the join appears in the Query Builder pane, running. This article will provide a full overview, with examples of the SQL Outer join, including the full, right and left outer join as well as cover the union between SQL left and right outer joins. In MicroStrategy Analytics Developer 9. Open MicroStrategy Developer. The options for this property are. From what you have described an outer join on the metrics seems to be the right thing to do. 0 SP2 supports FULL OUTER JOIN syntax between tables in the FROM clause. JOINS can also be used in other clauses such as GROUP BY, WHERE, SUB. Go to Metric Options again and note that the metric join still says Outer Join. You can configure properties such as SQL join types, SQL inserts, table creation, Cartesian join evaluation, check for null values, and so on. Given a choice, it is recommended to use a JOIN over a sub query. FROM t1 FULL OUTER JOIN t2 ON t1. itemkey = sub. If you created two facts with the condition inside than you don't need the conditional metrics and the outer join –This article describes how SQL Global Optimization handles inner versus outer joins between metrics in MicroStrategy. Add a filter condition based on Call Center attribute. SQL RANK() function examples. Each basket stores zero or more fruits and each fruit can be stored in zero or one basket. To pick up the fix, upgrade to MicroStrategy 2021 or above and enable project level setting "Data Engine Version" to 2021 or above. [CATEGORY_ID] = a12. When MicroStrategy SQL Generation Engine tries to identify the common key to join the tables in the final pass, the mismatch between the keys causes the Engine to join on only one attribute (Customer City). In the right corner of the dashboard, change. Our solutions work to guide towards best practices and provide guidance to the user community. This means you can manually change the suffix to . SQL FULL OUTER JOIN example: In this example, the clause returns all rows from both the customers and orders tables. Repeat with Response. The following table lists folders and files of interest that are included in the default directory structure after an installation of Developer. There are mainly 4 different types of JOINS in SQL server. x releases, and the new Multi-table Data Import (MTDI) cubes. Click OK. •. This pairs rows from each dataset together. In the same pass and between 2 different tables. Full Outer Join Support = Outer-Join . 0 for databases that do not support Full Outer Joins Number of Views 1. Normal join In normal join, only matching rows are returned from both the sources. The options for this property are No support Support, which assumes that. id = p. Go to TOOLS > Report Options. 10 it is possible for users to view the query details of a visualization in a dossier. Having the following hierarchy: Country > Distribution Center > Calling Center > Full Outer Join Support is an advanced property that is hidden by default. thread395-807711. Watch the video below to see some creative use cases and learn how to build! 5 new visualizations unlock meaningful ways to explore your data including Modern Grid, Sankey, Time Series, Multi-Metric KPI,. FROM CUSTOMER, ADDRESS. The following SQL statement selects all customers, and all orders: SELECT Customers. Perform a left outer join first to keep all attribute elements at the Store, Day, and Item level, then aggregate the data to the Store and Month level. Follow the steps below. id = Price. mstr suffix. 11 and earlier releases. Two other VLDB properties, Downward Outer Join Option and Preserve All Lookup Table Elements, have an option to apply the filter. " button under the. There's a reason we're at the top of the list. In order to resolve this issue using MicroStrategy, I enabled the VLDB property- ‘Cartesian Join Warning’ to ‘Execute’. (For information on object levels, see Order of Precedence . SYMPTOM: If a report contains multiple metrics and more than one of the metrics has a join type of 'outer,' the MicroStrategy SQL Generation Engine 9. The Cartesian Join Governing setting is available under Joins. Assuming you're joining on columns with no duplicates, which is a very common case: An inner join of A and B gives the result of A intersect B, i. Create three reports named A (with attribute A), A&B (with attribute A and B),A&C (with attribute A and C) Create a dashboard based on the three reports created in last step. Cube Subsetting Instruction (CSI) Steps to Reproduce. Check Query DetailsThis document describes how to use the Logical View feature introduced in MicroStrategy to specify an outer join between two attribute lookup tables when only attributes are on a report. Chapters. There's a reason we're at the top of the list. The strength of NSS lies in its outstanding model. RIGHT OUTER JOIN/RIGHT JOIN. This article is to introduce a workaround to achieve the attribute left outer join on MicroStrategy Web. LEFT OUTER JOIN. RIGHT [OUTER] JOIN. Cross joins appear when two tables do not have any common key attributes between them in which they can inner join. Great idea, but does not work! From a no apparent reason, no metric dimensioned in MicroStrategy can be “conducting”, ie standing in a LEFT OUTER JOIN on the left side. doc_id, a. All rows of the intermediate table are preserved. I understand that might only work with varying endings to the query, unlike other suggestions with '%' + b + '%', but is. A ORDER BY table_A. You can right-click the line representing the join and select one of the four join types described above to modify the join type. Join common key on both sides. How to use Guacamole to copy and paste text or files in MicroStrategy on AWS; All new Download site is now available!Community & Support Search Discussions Open A Case View My CasesFull Outer Join not returning unmatched join field values SQL SERVER 2005. Before MicroStrategy 2020, users may encounter bad performance when running a dossier with Metrics defined on Attribute. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. When no matching rows. Join queries. This article addresses a case which fails with a cross join when an unrelated filter is applied. Trending Articles. 52K KB440718: Aggregate from base derived metric with an attribute to ignore filter does not get ignored in the metric calcula… Select VLDB Properties from the Data menu to access the VLDB Properties (Report) dialog box. I have one table with a column ID and SERVICE_TYPE_TEXT, and another table with columns. (See Example 1: Same attributes, same filter) Example 2: Same attributes with different element values. The following VLDB settings will enable. inner join [LU_CATEGORY] a12 on (pa11. Full Outer Join Support is an advanced property that is. In MicroStrategy SDK 9. There's a reason we're at the top of the list. PRIME stands for Parallel Relational In-Memory Engine, and it engulfs two types of in-memory cubes: OLAP cubes, or the traditional Intelligent Cubes that have existed since 9. x may need to. x, once a custom group and a level metric are add into a report, though you enable join type to outer join, null value still can’t been seen. The customers with cust_id “3” have no orders, and the orders with order_id “103” has an id order and no matching customer, so their respective columns contain NULL values in the result. To Define a Join Between the Columns of Two Tables. A metric join setting determines how data is combined by applying a specific type of join, inner or outer. sql File. 0, this Feature Flag is removed and replaced with project level setting called "Data Engine Version". Report level In Developer. A simple idea would be to modify the metric by means of dimensionality, namely, the LEFT OUTER JOIN attributes with the setting ignore add / None. txt. Authors can add links via Desktop, Web, or Workstation. When no matching rows exist for a row in the left table, the columns of the right table will have NULLs for those records. There's a reason we're at the top of the list. Go to Web, create a new dashboard, and check the join behavior checkbox. sorry, I missed one step, you should put the metrics in outer join, because, as you noticed, it's possible that one of them returns no values. When writing queries with our server LIKE or INSTR (or CHARINDEX in T-SQL) takes too long, so we use LEFT like in the following structure: select * from little left join big on left ( big. On the Freeform Sources tab, select one of the following options: To create an Intelligent Cube by creating SQL statements using the Freeform SQL Editor. x: The report returns the following: Notice in the screen shot above that the Data for Project B is missing. 0: The SQL for a Report shows that two identical tables do a full outer join twice. Here the filtered attributes are lost because of the outer join and all the years are shown on the report, but the metric is only calculated for 1997. MicroStrategy Engine provides the capability to switch the order of. 0 SP2 supports FULL OUTER JOIN syntax between tables in the FROM clause. ORDER BY. The following procedure includes these steps. DealSizeUnit should be a metric that an attribute. Let’s dive in. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. Login MicroStrategy Developer 2. FULL OUTER JOIN. WHERE CUSTOMER. Now my objective is to generate an SQL which will look like the following: select. This method exists as attribute only outer joins will not be generated on their own by the MicroStrategy SQL engine. CAUSE This is a known issue in MicroStrategy 10. When you specify a table to join with a fact, you are creating a table relation to extend a fact. Loading × Sorry to interruptA metric join setting determines how data is combined by applying a specific type of join, inner or outer. x, a metric's join type is defined by a property called 'Metric Join Type' within the 'VLDB Select' property set. Click Demo. 6. This article is to introduce a workaround to achieve the attribute left outer join on MicroStrategy Web. CAUSE. SELECT Installed. This is appropriate if the metric should be outer joined in every circumstance. This can cause outer joins. Do you first pass and left outer (or Right or full, which ever floats your boat) to the second pass on the one column that you want. 7. The unmatched rows are returned with the NULL keyword. Execute a report. For example, setting Metric Join type to "Outer" at the report level (Metric editor > Tool > Metric Join Type) overwrites the Metric Join Type set at the Database Instance Level: The subject of Outer Joins is a very broad one, however, as a continuation of. Full outer join support. The SQL passes will then left outer join and give you the results you want. For these databases, MicroStrategy implements a technique of analyzing each metric's result pass to obtain all the distinct attribute elements that are required to preserve the rows. Step 2) Loading and Displaying Data. Two identical tables for a full outer join twice when metric join type is set to Outer Join and. In the future, please include the complete table definition in your questions (the CREATE TABLE part). You can right-click the line representing the join and select one of the four join types described above to modify the join type. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. There are mainly two types of joins in DBMS 1) Inner Join 2) Outer Join. Select Support. A table relation defines a join on tables. This issue has been addressed in MicroStrategy 2021. For more details on enabling the setting, refer to Change Data Engine Version After the fix, metric outer join works and data returns. CREATE TABLE fruits ( fruit_id INTEGER PRIMARY KEY , fruit_name. Why MicroStrategy Why MicroStrategy; Customer Stories; PlatformThere's a reason we're at the top of the list. Levels at Which You Can Set This . Create a new dataset. id GROUP BY first_name, last_name; Explanation: This is an example of using FULL JOIN as well as joining more than two tables. LEFT JOIN; RIGHT JOIN; FULL JOIN; 1. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. Why MicroStrategy Why MicroStrategy; Customer Stories; PlatformAs a result, the metrics' join types fall back to the project default, which is inner join for MicroStrategy Tutorial. To include the left outer join clause, follow the steps below: The following schema shows which setting takes precedence when set at different levels. Loading. Join common attributes (reduced) on both sides. ACTION The downward outer join algorithm introduces a cost, in terms of performance and an inflated number of result rows, in exchange for improved data reliability. The only joins supported by MicroStrategy use the = operator. In 11. For example: Metric, by default is Inner Join. The year_date attribute from table 2 is added to the grid. Overview of SQL FULL OUTER JOIN. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. Preserve All Final Pass Result Elements. FULL JOIN makes duplicate records for each match on either side. You can use. Page-by makes viewing a report easier than scrolling through long lists of data. After the project information is. The MicroStrategy SQL Engine applies the designated join type to the data pulled from your data source's tables. LEFT [OUTER] JOIN. Result: Acts mostly as one dataset, but missing values are. Hi, I have the following query in microstrategy report . solutions Forum Left outer joins iolaper (MIS) (OP) 19 Jul 04 09:53 Hello guys, I am trying to generate a. r/PowerBI. StoreId in ('12345') You can then add in Item as a second INNER JOIN, relating it. In this situation the presence of Year_date on the grid limits the data to just rows that exist in table 2 which is why the year 2016 is not seen. Another way is to use the Lowest level attribute in the report object pane. Attribute to Join When Key From Neither Side can be Supported by the Other Side. First: drop the client column from ClientIDPrefixSumPurchased and ClientIDPrefixSumInstalled both from the select clause and the group by. CUSTOMER_ID (+); Now, I have created an attribute called customer Id at MSTR and defined the join (Through checking the box). Pre/Post Statements Drop Database Connection=Do not drop database connection after running user defined SQL [when using pre/post SQL]. Creating a template with full outer join support enabled can save report developers time when requiring full outer joins. However, if the Full Outer Join Support is NO, then the left outer join is used to simulate a full outer join. However, enabling full outer join support for specific reports is recommended if full outer joins are only used for a small to moderate amount of reporting needs. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. x, a metric's join type is defined by a property called 'Metric Join Type' within the 'VLDB Select' property set. ( How?) Expand Database instances. MicroStrategy is the leading enterprise business intelligence tool with its mission statement to make every enterprise a more intelligent enterprise. In the MicroStrategy Tutorial, a report with the Subcategory attribute and the Freight and Discount metrics generates the following SQL (using Microsoft SQL Server): select a13. In the Tutorial project, the user needs to create a report, for. x A report defined as shown below returns no data in Microstrategy 10. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. •. This will be your lookup table for your Item attribute. The join type places conditions on the data to be displayed in the report. This article describes how out joins ignore the filter in the final pass in MicroStrategy SQL Generation Engine 10. No support; Support, which assumes that the Join Type VLDB setting is Join 92; any other value in Join Type is ignored; Use default inherited value. e. When the metric join type is set to Outer Join and the SQL Global Optimization is set to Level 4, extra SQL passes are generated. So in 9. Query Details also explains that the Attribute Outer Join is correctly applied, in blue below. SYMPTOM. Sub queries. Options for the VLDB property, Attribute to Join When Key From Neither Side can be Supported by the Other Side, can no longer be selected once you upgrade your data engine version to 2021. EQUI JOIN; SELF JOIN; 2. doc_id, a. Clear the Use default inherited value check box. However, in the third pass, when combining the results from the first two passes to generate data for Unit Sales, a full outer join between pass 1 and 2 is performed. KB31133: Join conditions are omitted in the calculation of nested aggregation metrics in MicroStrategy SQL Generation Engine. x. Those intermediate passes will then be merged in a last pass (if metric join type is set to outer then the last pass is a full outer join). When talking about Theta joins the following operators are used < , ≤ , > , ≥ , ≠. Use default inherited value. 0 to create the outer join. The default join behavior will be "Use minimum relation," regardless of what the setting is set to. 7). CREATE TEMPORARY TABLE. Here is the workaround to achieve the attribute left outer join on MicroStrategy Web. 4. Why MicroStrategy Why MicroStrategy; Customer Stories; PlatformSimilar to scenario 1, three passes are generated. key. Similar to scenario 1, three passes are generated. Click on 'OK' and save the Attribute. Change the join type from inner to outer. For attributes, the default join type is Outer Join. An inner join is a standard type of join. 1, it is possible to identify specific attributes as having an incomplete lookup table by setting the “Preserve all final pass result elements” VLDB property within the attribute. And I have another attribute called Address from Address table which is straightforward. For a compound join, Intelligence Server joins the data in the datasets as described below: If the datasets have any of the same attributes, the common attribute elements are matched. The SQL you get will be:Syntax : SELECT column_name (s) FROM table1 RIGHT JOIN table2 ON table1. In MicroStrategy Analytics Developer 9. For example, consider the relationship between three attributes: Promotion, Item, and Quarter. An outer join includes data that applies to all components. Also you can take advantage of Metric Dimensionality i. Enable optimization to remove repeated tables in full outer join and left outer join passes. Why is this happening? This VLDB property becomes obsolete with an upgrade to a data engine version of 2021 or later. This is due to the fact that the user allocates resources in anticipation of a very large amount of data (even if the string is only a few hundred. On the duplicated visualization, go to Metric Options and change outer join for both the metrics to be inner join. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. Let’s take an example of using the FULL OUTER JOIN clause to see how it works. Ranked #1 for Enterprise Analytics in 2022 Gartner Critical Capabilities Report. Inner and outer joins are discussed with examples. If you are upgrading to MicroStrategy 11. Therefore, SQL is generated for the filtering report using an inner join between the two metrics, and since the metrics have no attribute elements in common, all data are excluded. contacttypeid=b.