[FREQUENTLY ASK] Looker Interview Questions and Answers

1. What is a Looker used for?

Ans:

Looker is a powerful business intelligence (BI) tool that can help to business develop insightful visualizations. It offers the user-friendly workflow, is a completely browser-based and facilitates a dashboard collaboration.

2. What is a Google Looker?

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Looker for a Google Cloud Platform can help anyone in a business to quickly analyse and find insights in a datasets. Looker can make it simple to build a data exploration platform that makes on data accessible in a meaningful, intuitive way for an organization.

3. Is Looker Google product?

Ans:

Today, company announced that the deal has an officially closed and Looker is part of a Google Cloud Platform. While Kurian was happy to announce that a Looker was officially part of a Google family, he made it clear in a blog post that the analytics arm would continue to a support a multiple cloud vendors beyond Google.

4. Is Looker good tool?

Ans:

A trusted data model supports a Looker data platform and consistently defines key business rules and metrics and granular user the permissions for organization. Customers tell us that Looker’s flexible, powerful, foundation is their key to delivering a actionable insights to internal and external customers.

5. What are noticeable differences can find upon comparing DTS and SSIS?

Ans:

SSIS	DTS
SSIS can handle the lot of errors irrespective of their complexity, size, and source.	On other side, an error handling capacity of DTS is limited.
SSIS comes with the excellent development wizard.	The same is absent in a case of DTS.

6. Who started a Looker?

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A Lloyd Tabb, a Ben Porterfield.

7. Is memory a Looker?

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Tableau is optimized for a in-memory data extracts, which, over time, creates management and governance challenges. Looker’s centralized, an agile modeling layer creates a trusted environment for all users to the interact with — all without any data extraction.

8.Does a Looker use SQL?

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Fundamentally, Looker is the tool that generates SQL queries and submits them against database connection. Looker formulates a SQL queries based on LookML project that explains the relationship between the tables and columns in a database.

9. Is a Looker publicly traded?

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Now Looker, a Santa Cruz, Calif. -based supplier of a analytics tools, is taking on the publicly-traded Seattle-based Tableau Software in a $18 billion market for a data analytics that includes business intelligence (BI) and also data visualization, according to Gartner.

10. What is a SSIS?

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SSIS is an abbreviation for SQL Server Integration Service. It is the component of the Microsoft SQL Server database and is used to build workflows for a data migration tasks. It is an ETL tool that extracts a data from various sources, transforms it, and loads it in different destination.

11.Can connect a Tableau to looker?

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Tableau is integrating with the Looker to help customers connect with governed data and build a flexible of data environment that scales and adapts with an volving needs.

12. Why is a Google looking?

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Looker gives the tools to power a multitude of a data experiences, from modern business intelligence and embedded analytics to workflow integrations and custom data apps. Regardless of where a data resides, Looker offers a unified surface to access a truest, most up-to-date version of a company’s data.

13. Compare No Cache Mode with a Partial Cache Mode?

Ans:

No Cache mode	Partial Cache Mode
The No Cache Mode is situation when a rows are not generally cached.	Upon adding a new rows, a SSIS starts analyzing a database.
Users can customize this mode and can allow rows to be cached. However, this is one after one and thus consumes the lot of time.	The rows are only considered or allowed to enter only if they match with a currently existing data, and sometimes it creates a issues when a rows come instantly one after one.

14. What language is a Looker built in?

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Looker makes use of simple modeling language called a LookML that lets data teams explain the relationships in their database so business users can explore, save, and download data without needing to know a SQL.

15. What language is a looker?

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LookML:LookML is language for explaining dimensions, aggregates, calculations, and data relationships in the SQL database. Looker uses a model written in a LookML to construct the SQL queries against a specific database.

16. How does a Google looker work?

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How Looker a works. Looker let’s data experts at every organization describe their data using a lightweight modeling language called a LookML. LookML tells a Looker how to query data, so everyone in an organization can made easy-to-read reports and dashboards to an explore patterns of data.

17. Why is a looker so slow?

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Looker Dashboards load in a browser. … Some components are more memory intensive than are SQL related — these can cause a slow performance in a dashboards: Data volume has a greatest impact on performance. The more data that is returned in the individual element, more memory resources will be consumed.

18. How do deploy a looker?

Ans:

• Install Looker: Add a Looker to a server. Configure a Looker startup options.
• Enable a secure database access.
• Configure a database for Looker.
• Connect Looker to a database.
• Test a database connectivity.
• Configure a Looker sign-in options.

19. Which Container In Package Is Allowed For a Logging Of Information To A Package Log?

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Every box or an assignment is permitted to try this. However, need to be assigned throughout a preliminary stage of the operation for this.

20. Explain categories of data flow?

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Sources : The sources can be an excel files, flat files, XML files, Relational databases, etc.

Transformations : Filter a data based on some calculations, changing a format of the data, etc.

Destinations : Destinations can be an excel files, flat files, PDF files, XML files, relational databases, etc.

21. Can name a few tools that can deploy for a Data Analysis?

Ans:

The most generally used tools are RapidMiner, Node XL, Wolfram Alpha, KNIME, SOLVER, Tableau, as well as a Fusion Tables by a Google.

22. What Are The Basic Issues In a Data That Can Create A Lot Of Trouble For a Data Analyst?

Ans:

One of the largest hassle creators is a duplicate entries. Although this will be eliminated, there may be a no full accuracy viable. This is because an identical data is commonly available in a distinctive layout or in various sentences. The not unusual misspelling is the some other fundamental problem author. Also, various cost can create a ton of a troubles. Moreover, values which might be unlawful, lacking and can not be recognized can beautify chances of a diverse mistakes and an equal affect the exceptional as much as of outstanding volume.

23. How do create a view from a table in a Looker?

Ans:

• Adding a new view from the existing database table.
• Within the project, click + at the top of project file list in the Looker IDE, or can click a folder’s menu to create a file inside the folder.
• Click Create a View From Table.
• Looker displays a list of tables associated with the one of the connections.

24. How do get started with the Looker?

Ans:

Visit connect.looker.com to get be started.

Since this is the new platform, need to create new account, and the first time log in we’ll ask about how use Looker in a role.

25. Why is a BigQuery so fast?

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Unprecedented performance: Columnar Storage. Data is a stored in a columnar storage fashion which madeit possible to achieve a more high compression a ratio and scan throughput. Tree Architecture is used for a dispatching queries and aggregating results across thousands of machines in few seconds.

26. What is NoSQL database?

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NoSQL, also referred to as a “not only SQL”, “noSQL”, is an approach to database design that enables a storage and querying of a data outside traditional structures found in a relational databases.

27. Why is a BigQuery fast?

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Due to separation between a compute and storage layers, BigQuery requires ultra-fast network which can deliver a terabytes of data in seconds directly from storage into the computers for running Dremel jobs. Google’s Jupiter network enables a BigQuery service to utilize 1 Petabit/sec of total bisection of bandwidth.

28. Is a looker an open source?

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A Looker Open Source · GitHub.

29. What is similar to a Looker?

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• Competitors and Alternatives to a Looker
• A Microsoft Power BI.
• Tableau Desktop.
• Qlik Sense.
• A SAP BusinessObjects BI Suite.
• Sisense Fusion Analytics.
• A TIBCO Spotfire.
• Microstrategy.
• IBM Cognos Analytics.

30. What are the advantages of Looker BI?

Ans:

• It generates base model so can work on a relationships .
• All employees in an organization can have centralized view of metrics.
• Can create simple to read dashboards that allow users to find a patterns .
• It connects directly to a database instead of loading a data from it.
• Can share the generated reports across an organization.

31. What are the Looker blocks?

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Looker Blocks™ are pre-built data models for the common analytical patterns and data sources. … From an optimized SQL patterns to fully built-out data models, Looker blocks can be used as starting point for the quick and flexible data modeling in a Looker.

32. Who uses a Looker?

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Over 1,600 industry-leading and an innovative companies like Sony, Amazon, The Economist, IBM, Spotify, Etsy, Lyft and a Kickstarter have trusted Looker to power their of data-driven cultures.

33. What is a Snowflake Looker?

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Snowflake is the fully-managed Cloud MPP data warehouse that enables a users to spin up as more virtual warehouses as they need to parallelize and isolate a performance of an individual queries.

34. What is a Looker app?

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The Looker mobile application allows users to the quickly view recently viewed and favorite of Looks and dashboards, view boards they follow, browse content that is stored in a folders, and share the content on a mobile device.

35. Is Looker no code?

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As somebody who built a lot of a Looker, it is not no-code for this more reason. It’s why Looker data model is stored in a hand-editable code and the under version control.

36. How much did a Looker sell for?

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When a Google announced that it was acquiring a data analytics startup Looker for the $2.6 billion, it was a big deal on the couple of levels.

37. Why is a Looker created LookML?

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LookML empowers a data professionals to an empower others. The “data model” that Looker helps to build enables non-technical users to do their jobs–building dashboards, drilling to a row-level detail, and accessing difficult metrics–without having to worry about what’s behind a curtain.

38. What is Mean By The Term Data Cleansing?

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It is nothing but the other call of statistics are cleansing system. Basically, there are numerous methods which might be taken into a consideration for putting off an inconsistencies and mistakes from a datasets. Combination of these types of approaches is considered as a information cleansing. Basically, all approaches or methods have a comparable target and that i.E. To boost a quality of statistics.

39. What is a tile in looker?

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Visit Dashboards documentation page to learn more about a Looker’s new dashboard experience. … Tiles are visualizations that are added to a dashboard from the Explore or a Look. Tiles can be a Look-linked or query-based. Query tiles vary from Look-linked tiles because they are stored only on a dashboards.

40. Explain about OLTP

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Online transaction processing (OLTP) supports a data processing of transaction-oriented applications. It focuses on a day to day transactions of an organization. It involves an updating, inserting, deleting small chunks of data in the database. Since it operates on a data of small size, the processing speed is be faster.

41. What is a Looker development mode?

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Development Mode allows to make a changes to LookML files and to preview how they will affect content on a instance. In Development Mode, can see the effects of changes to a project files in an Explore area of Looker.

42. What is a Looker good for?

Ans:

Looker is the powerful business intelligence (BI) tool that can help business develop an insightful visualizations. It offers user-friendly workflow, is completely a browser-based and facilitates a dashboard collaboration.

43. What doesa Looker integrate with?

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Looker connects with a Redshift, Snowflake, BigQuery, and 50+ supported SQL dialects, so can link to a multiple databases, avoid database lock-in, and maintaina multi cloud data environments.

44. What is Understand By a Term Logistic Regression?

Ans:

It is basically approach this is considered for a correct verification of a dataset that includes a impartial variables. The verification level is based on how properly very last final results depends on these variables. It is not constantly clean to a change them once described.

45. How much data can Looker be handle?

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Without the set row limit, Looker supports up to a 5,000 rows.

46. How long does it take to an implement Looker?

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These features are to be straightforward to add, as the foundation comes out of a box from Looker. Check out how a Looker customer SupporT trends built an embedded analytics solution in only 6 months and took just a 2 weeks to implement Looker visualizations.

47. Where is a Looker hosted?

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Deployment of Looker-hosted instances has historically been on a Looker’s virtual private cloud (VPC) on an Amazon Web Service (AWS). Beginning in November, customers can choose between hosting on the AWS or the Google Cloud Platform (GCP). Customers can even self-host on a private infrastructure if necessary.

48. Can a self host Looker?

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In self-hosted Looker deployment, may need to deploy the ancillary services in a cloud to access these features.

49. Where does a Looker run?

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Looker runs as Java virtual machine. If Looker instance is on VMware guest, there may need to do a some performance tuning.

50. What are cache modes available?

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Full cache mode : All values will be cached.

Partial cache mode : Only a distinct values will be cached.

No-cache mode : No data will cached.

51. What is PDT database?

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Background. A Persistent Derived Table is table that Looker can create and manage in the target database. The table is loaded with a data from a SQL statement explained in a view file, and is refreshed on the regular basis.

52. How many types of a views are there?

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There are a total of 4 types of views, based on a way in which the view is implemented and methods that are permitted for the accessing the view data. They are – Database Views, Projection Views, Maintenance Views, and also Helps Views,.

53. How do view a SQL in Looker?

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Click a Database tab. In SQL Runner, click a gear for a table and select an Explore Table. Looker creates a temporary model with a view for the table, then displays a Explore. Looker provides the dimension field for every column in the table.

54. Do need to know a SQL to use Looker?

Ans:

Writing a LookML requires an understanding of a SQL queries. don’t have to be SQL guru, and even beginners can create a powerful Looker models. But, in a general, deeper go in a LookML, the more benefit from a deeper knowledge of a SQL.

55. What is the offset in a looker?

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As of a Looker 3.36, have introduced an offset_list function. This function allows to create a list from the group of rows in a column, and then aggregate over that list. The offset function in a table calculations allows to reference a single value in previous or following row.

56. What is looker in a GCP?

Ans:

• Looker is the enterprise platform for a business intelligence, data applications, and embedded analytics.
• Looker helps to explore, share, and visualize the company’s data so that can make a better business decisions.

57. Is a Looker SAAS product?

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Looker is a modern business intelligence and also data exploration platform that allows users of all skill levels to simply explore and visualize data and find a insights.

58. How does a Looker connect to the database?

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Select Connections from a Database section in an Admin panel. On Connections page, click Add Connection button. Looker displays the Connection to Settings page. The fields that Connection Settings page displays depend on a dialect setting.

59. How does a Looker connect to Snowflake?

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Configuring OAuth for a Snowflake connections. Looker supports the OAuth for Snowflake connections, meaning that every Looker user authenticates in to Snowflake and authorizes the Looker to run queries on a database with their own Snowflake user account.

60. Define a drill-down analysis?

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Drill down is a capability provided by a most BI tools. It helps in viewing a data in a detailed manner and gives in-depth insights. And can drill-down on a component in the report or dashboard to get more granular details of it.

61. What is explored in a Looker?

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In Looker, users can see the Explores listed in the Explore menu: By convention, Explores are declared in a model file. The example below demonstrates as a declaration for an orders Explore for e-commerce database. The views orders and customers are explained elsewhere, in their respective of view files.

62. What is field picker in Looker?

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A Github repo API docs. Embedding on-the-fly visualization, as opposed to the saved look, gives a complete flexibility to programmatically explain the data set and look and feel of embedded table or graph.

63. What are measures in a Looker?

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Post-SQL measures are special measure types that perform a specific calculations after Looker has been generated query SQL. They can reference only a numeric measures or numeric dimensions. Anad cannot use a filters parameter with these measure types.

64. Can Looker connect to a SQL Server?

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Looker requires “SQL Server Authentication” on a MSSQL server. If a MSSQL server is configured as “Windows Integrated Authentication” only, change server configuration to “Windows Integrated Authentication and also SQL Server Authentication.” If this is not a set properly Looker will be unable to the connect.

65. Can Looker connect to the excel?

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Although Looker does not connect a directly to an Excel spreadsheet, there are ways to upload a data by derived table. The secondary method utilizes a CONCATENATE function to create series of SELECT statements to ultimately create SQL based derived table.

66. What is a Snowsight?

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Snowsight, SQL Worksheets replacement, is designed to a support data analyst activities. Snowsight is available in a new Snowflake web interface.

67. How do get to SQL runner in a looker?

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• Navigating to a SQL Runner.
• In a Develop menu, select SQL Runner.
• From Explore, click SQL on a Data bar to see the SQL. Then click Open in az SQL Runner to see the query in a SQL Runner, or click Explain in SQL Runner to open a SQL.
• Runner and request a database’s execution plan for a query.

68. What is a role of Snowflake?

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Snowflake uses a roles to control access to objects in a system: Roles are granted access privileges for an objects in the system (databases, tables, etc.). Roles are granted to the users to enable them to create, modify, and use a objects for which the roles have privileges.

69. What is Looker model?

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In Looker, a model comprises the combination of related Explores and dashboards. … Instead, any file placed in a Models section of the Looker IDE explains a model. The model name is taken from a filename and must be unique across an instance, even within various projects.

70. What is the use of Rebuild Derived Tables and Run?

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The “Rebuild Derived Tables and Run” button is used to rebuild all the persistent derived tables given in a query. It will also rebuild all upstream PDTs.

71. Why is a LookML built?

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LookML is a built for today’s complex data. Bad tools just make a complexity harder to deal with. LookML is the powerful tool for power users that helps them capture that complexity–whether an inequality joins, many-to-many relationships, multi-level aggregation, or anything else–and render it invisible to the end users.

72. What is cross filter in a Looker?

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Cross-filtering makes it simpler and more intuitive for a viewers of dashboards to interact with the dashboard’s data and understand how one metric affects another. With a cross-filtering, users can click a data point in a one dashboard tile to have all dashboard tiles automatically filter on that value.

73. How do run a query in a looker?

Ans:

To run a query against a LookML model in the SQL Runner:

• Click a Model tab.
• Select a model want to query.
• Click in a SQL Query area and enter a SQL query using LookML fields.
• Optionally, double-click on a view in view list to include the view in a query at the cursor location

74. How do connect to AWS looker?

Ans:

• Ensure that have the following: A pair of an Amazon AWS access keys.
• In an Admin section of Looker, select Connections, then a New Connection.
• Fill out connection details: Name: Specify a name of the connection.

75. What is a Looker API?

Ans:

The Looker API is secure, “RESTful” application programming interface for managing a Looker instance and fetching data through a Looker data platform. With Looker API, can write applications or automation scripts to provision a new Looker user accounts, run queries, schedule reports, etc.

76. Can upload CSV to a looker?

Ans:

Can share and access the data in a text, JSON, CSV, and HTML formats by changing a format extension of an URL.

77. Can looker connect to a CSV?

Ans:

Starting in a Looker 7.4, can use a Looker’s new, secure, OAuth-based action to send a CSVs directly from Looker to Google Sheets on a one-off or recurring basis

78. How do share a looker Dashboard link?

Ans:

• Sharing a dashboard’s of URL
• Selecting a Get link option from a dashboard’s three-dot menu reveals a pop-up that contains a link to a dashboard, which can be copied and shared.

79. What is a GCP Looker?

Ans:

Looker is an enterprise platform for a business intelligence, data applications, and embedded analytics. Looker helps to explore, share, and visualize a company’s data so that can make a better business decisions.

80. Does Looker require access to a scratch schema to write ephemeral derived tables?

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No, don’t have to set up scratch schema. For a MySQL family of databases, need to perform a some additional setup to allow ephemeral derived tables.

81. What is a derived table in a Looker?

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In Looker, a derived table is the query whose results are used as if it were an actual table in a database. For example, let’s say have a database table called orders that has a many columns.

82. What are boards in a looker?

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• Boards in a Looker provide a way for teams to find a curated dashboards and Looks. Dashboards and Looks, which are stored in the folders, can be pinned to a multiple boards.
• A Board access levels
• Manage access to a board.
• Organize and manage content on a board.
• Pin and remove a Looks and dashboards.
• Delete a board

83. What does a Teradata do?

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Teradata is enterprise software company that develops and sells a database analytics software subscriptions. The company provides a three main services: business analytics, cloud products, and consulting.

84. What is use of a BigQuery?

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BigQuery is a fully-managed enterprise data warehouse that helps to manage and analyze a data with built-in features like a machine learning, geospatial analysis, and business intelligence.

85. How can improve a Looker performance?

Ans:

Optimize Looker Server Performance Use a dashboard auto refresh feature strategically. If dashboard uses a auto refresh, make sure it refreshes no faster than an ETL processes running behind a scenes. Use a pivots strategically, and avoid over-using pivots within the dashboard tiles and Looks.

86. Is SQL Looker?

Ans:

Fundamentally, Looker is the tool that generates SQL queries and submits them against database connection. Looker formulates a SQL queries based on a LookML project that explains the relationship between tables and columns in a database.

87. What is the dimension in Looker?

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In a Looker, a dimension is the groupable field and can be used to filter a query results. It can be: An attribute, which has direct association to a column in underlying table. A fact or a numerical value. A derived value, computed based on a values of other fields in single row.

88. What are the Looker models?

Ans:

In a Looker, a model comprises a combination of a related Explores and dashboards. Unlike the other LookML elements, a model is not declared with the specific “model” parameter. Instead, any file placed in a Models section of the Looker IDE explains a model.

89. What is pivot in a Looker?

Ans:

Looker supports up to a 200 pivoted values. To pivot Explore results by the dimension: Hover over the dimension in a field picker and click the pivot icon. … To unpivot a results, click the field’s gear icon and select a Unpivot option, or click the dimension’s pivot icon again in a field picker.

90.What are the Native Derived Tables (NDTs)?

Ans:

The Native derived tables (NDTs) is explained in the LookML. And can create a native derived table by specifying a explore parameter on the base table with the desired columns.

91. How do make a bucket in Looker?

Ans:

• Using a tier dimension type.
• Using a case parameter.
• Using SQL CASE WHEN statement in a SQL parameter of a LookML field.

92. What is a Group label in Looker?

Ans:

The group_label parameter specifies a label to use as a heading in an Explore menu for this Explore. Instead of every Explore being listed under its model’s name, can list an Explore under new group label or under an another model’s name.

93. What is view label?

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View labels let communicate an information about drawings, such as a view names and scale. View labels use tags to an add content, but can also type text in label.

94. Define pivoting?

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Looking at data in a multiple dimensions makes it simple to consume the data visually. To change dimensions, can use a pivot option that turns a dimension into a column. And can only change a pivoted dimensions order by changing the sort order.

95 Explain a user flow analysis by heap in Looker?

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Heap captures user behavior like a clicks, taps, gestures, and more across websites and applications automatically. It allows a data enrichment with the custom APIs. This will help in analyzing a user actions and present them visually.

96. What are important steps of an analytics project?

Ans:

• Data exploration
• Data definition.
• Data modeling
• Data validation
• Data preparation

97.Can use templated filters in a PDTs?

Ans:

Using a templated filters is not usually recommended. The table will be a rebuilt every time the filter changes, and it causes lot of strain on the database.

98.Why are copies of tables created in a same PDT of a database?

Ans:

When change the SQL of a derived table and query it, a new copy of a table is built in a PDT. The table copies only get created when a SQL in dev mode is different from production mode.

99. What are tools do data analysts use?

Ans:

• Microsoft Excel.
• Python.
• R.
• Jupyter Notebook.
• Apache Spark.
• SAS.
• Microsoft Power BI.
• Tableau.

100. Name types of a Looker blocks?

Ans:

• Analytic blocks
• Source blocks
• Data blocks
• Data tools
• Viz blocks
• Embedded blocks