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Data Surfing is always confused with Data Analysis. There is a very thin line between Data Analysts and Data Surfers.

Data Surfing is normally done by non-technical people like management who doesn’t know how to write any kind of code to access data at database level.

Data Surfers normally stays at the level of Dashboards and Reports where they just click here and there to explore data for required information.

Business Intelligence (BI) tools came into being to cater Data Surfers World where data was required to be presented for non-technical people who could view data for decision making.

Era(s) for Data Surfers

• Static Reports: In the beginning, business users used to share their data requirements with IT who then used to create dashboards and reports. Those dashboards/ reports and data was not changeable, it was in paper format or in excel format or in text format etc., means after Go-Live if business want one more column or if latest data was required then the whole development cycle had to restart from scratch.
• Dynamic Reports: In the second era, BI tools came-in to cater for this gap. To start with, dashboards/ reports were still not changeable, but data was directly connected with backend databases, so data was always latest at front-end. This was a huge jump, as now, to view new data developer don’t have to recreate front-end again and again.
• Adhoc Reports: Latest era is where dashboards/ reports are also changeable. Now, end users and management can drag and drop tables and columns in dashboards/ reports.

“Semantic” is an ancient Greek word: σημαντικός sēmantikós, "significant" is the study of reference, meaning, or truth.

In Data World, Semantic layer is built for the sole purpose of supporting business users.

Semantic layer is to convert complex data models into simple and user-friendly interface for business users.

A semantic layer is the representation layer on top of databases, schema(s), tables and columns in such a way that Business users who have no technical know-how should be able to drag and drop required details on Dashboards. For drag and drop, first, one must assign business names to all databases, schema(s), tables and columns before exposing in BI tools. For example, there can be a column name as Date but the data in this column can be Date_Of_Birth or Transaction Date or Financial_Year_End_Data. Converting data models, column/ table/ schema/ database names as per business understanding is semantic process.

By now, we all know what Semantic Layer is, IT defines data elements for business ease. Then there came the era for Business folks defines data elements themselves based on their own understanding and now the latest approach is going towards Machine Learning Models define data element based on open-ended requirements.

A major difference between first two approaches vs Augmented Analytics is, first two were derived by humans either by IT or Business folks so there is always a factor of human era and at the same time human can be biased base on knowledge and information they possess about the business domain. On the other hand, Augmented Analytics is based on automated Machine Learning which learns the data elements while new data sets keep coming in.

The first approach was static as requirements were always coming from business and implemented by IT folks, so any change had a round robin effect.

As much as Data Filtering is simple as much as it’s so important in Data World.

‘Data Filtering is about reducing the number of rows while pull data from a table.’

On Cloud: In Cloud, resources i.e., compute power or RAM are just click away. In fact, now a days these can automatically increase based on your query requirements. So, if you are using Cloud then, STRICKLY, no one is allowed to run any query either in PROD, UAT or Dev environment without any filter, means in a SQL command one must use WHERE clause as each query is attached with a dollar value. In Cloud, filtering becomes THE FACTOR to maintain resources utilization at minimum, considering as mentioned each resource costs a dollar value.

On-Premises: In contrast of Cloud, resources i.e., compute power or RAM in on-premises systems is limited. To increase resources on premises there is a need for a complete buying cycle by procurement which takes months. With static resources, if someone runs a query without a filter, that query can hold onto all the available resources, locking the rest of the queries. This can create delays in providing other datasets to top management, means delays in decision making, means losing business opportunities, means loss and no one like losses right. In nutshell, in on-premises solutions, filter also is very critical. At the same time developers has the liberty to us any kind of query in development environment as size of data is limited and static.

Data Usability is the key to being a Data Driven Organization.

To better understand, let’s refer to the difference between Useful and Usable.

• Useful means e.g., a system is fulfilling the business requirements and able to perform all the operation tasks.
• Usable means e.g., how easy the system is for operational tasks i.e., how automated it is, which makes the operator’s life easy.

Let’s map it with Data World. Consider, the marketing team needs data from, let’s say, 5 source systems to send campaigns to premium bank customers. Now, dumping data from all 5 source systems at one centralized location like Data Lake might be USEFUL as all sort of data is available at one place but it’s not USABLE unless until it is not converted into a format which marketing team can easily use to send campaigns. In other words, unless data is not formatted in a Data Warehouse or a Data Mart or in a Semantic Layer, it might not be usable for relevant team.

Data Aggregation is the most used term in our daily lives whether it’s in office or in home, we use it everywhere.

‘Data Aggregation is about converting details into summarized format.’

For example, if someone asks you how many months there are in a year? You won’t be taking names of all the months rather you will answer, there are 12 months.

Referring to the image, if your manager asks how many installations our team has done, you rather sending left side details, you will send right side summarized report to your manager i.e., in-total there are 6 iOS and 3 Android installations.

As we normally use databases or data stores to store data, there are different aggregation functions normally used to summarize the data.

Aggregation Functions as per ISO Standards

• COUNT
• SUM
• AVG
• MIN
• MAX

Few other Aggregation Functions

• APPROX_COUNT_DISTINCT
• CHECKSUM_AGG
• COUNT_BIG
• GROUPING
• GROUPING_ID
• STDEV
• STDEVP
• STRING_AGG
• VAR, VARP

Data Serving is also known as the Serving Layer and it has been there since its inception but as technologies have matured, many new channels have been introduced to support this layer.

‘Serving Layer is last component of the Lambda Architecture.’

Lambda Architecture has been explained in separate topic, so we won’t go into details of it but referring to it, as mentioned above, it is the last layer which is exposed to End Users for reporting purposes. This Layer is, if not all the time but majorly designed based on business requirements.

We all know OLTP systems are not meant to be exposed for reporting purposes. In the current era, for reporting, there are many data stores available i.e., Data Warehouse, OLAP, Data Lake, NoSQL, Semantic layers but ideally Semantic Layer should be treated as Serving Layer.

To be more specific

• If Serving Layer is designed for specific business requirement then Semantic Layer is last layer.
• If the Serving Layer is designed for generic use then it can be Data Warehouse, OLAP, Data Lake, NoSQL etc.

Consumption layer is confused with Serving Layer due to its name. Folks relates it that the layer which is used by Consumers to extract data. The Layer which Consumers use to extract information is Serving layer (explained separately).

Consumption Layer, as its name says it all, is a layer which consumes or takes-in data from source systems. In the current era, due to huge amounts of data coming in every second from sources like social media, CCTV, images, audios, sensors data etc. technology was required to consume data on a fast pace in MPP mode.

Tools like Hadoop, Object Storage and many RDBMS are giving MPP features now a days.

In Lambda Architecture, Serving Layer is the last layer, Consumption Layer is the layer which process data from source till Serving layer.

In the image, Batch and Speed Layers are Consumption Layers. In an OLAP system, the consumption layer is Data Warehouse and Data Mart, considering there are OLAP Cubes and Semantic layers but in a Data Warehouse, consumption layer is Landing and Staging zone.

Canned Data is something which is readily available at one click. A dataset prepared based on business requirements i.e., if required in pre-aggregated format, in one accessible format.

The aim of canned data is to have a dataset that needs no more cleansing, no more wrangling, no more reconciliation etc. Aim is, User to just click it and data should be served.

Imagine Canned food, which are prepared and seals to be used anytime, anywhere, by anyone. Most of the canned food is ready to eat. Same is with Canned data, ready to use. OLAP Cubes are a perfect example of canned data where pre-calculated and pre-aggregated data is stored in a multi-dimensional table, ready to be consumed anytime.

‘Canned data can be refreshed with latest data using same existing data element.’

Canned Reports

Just like Canned Data, Canned Reports has the same approach where static designed reports are built for non-tech savvy stakeholders, who just want to click once and see the expected required output.

Adhoc Reports

Whereas Adhoc reports are for tech savvy users who know how to play with the BI tools and who also have business knowledge of data element shared in the tool. Using Adhoc reporting, users can build their own reports, dashboards by drag and drop exposed tables and columns. Users can slice and dice the reports. Users can drill-in and drill-out.

Tools like

• Oracle Forms, SSRS etc. are considered as Canned Reports generators.
• Tableau, Power BI, Qlik etc. are considered as Adhoc Reports generators.
• OBIEE, Cognos etc. are considered as Semi Canned and Semi Adhoc Reports generators.