SSC CGL GK Questions 2026

Apache Hive puts a table-like view over files stored in HDFS and lets an analyst write queries in HiveQL, a language close to SQL, which Hive then turns into jobs that run on the cluster, so that no Java programming is needed.

NoSQL databases drop the fixed table and row structure so that they can hold large and irregular data and spread it over many machines, and MongoDB is the best known document store, keeping records as documents in a format close to JSON.

Clustering is unsupervised because the data carries no labels: the algorithm itself groups similar records, k-means doing so by placing k centres and moving them until each record sits with its nearest centre.

ETL names the three steps through which data enters a warehouse: it is extracted from the operational systems that produced it, transformed so that formats, units, codes and duplicates are reconciled into one consistent shape, and then loaded into the warehouse tables.

It uses historical data with statistical models and machine learning to estimate what will probably happen next, such as which loan accounts are likely to slip into default or how much electricity a city will draw next summer.

Storage units climb in powers of two, each unit being 1,024 times the one below it, so 1,024 bytes make a kilobyte, 1,024 kilobytes a megabyte, 1,024 megabytes a gigabyte, 1,024 gigabytes a terabyte and 1,024 terabytes a petabyte.

The Apriori algorithm first finds the sets of items that appear together often enough to pass a support threshold, using the rule that any subset of a frequent set must itself be frequent, and then turns those frequent sets into rules measured by confidence.

In the process called Knowledge Discovery in Databases, or KDD, the stages run from selection of the relevant data, through cleaning and preprocessing, to transformation, then data mining, and finally interpretation and evaluation of what was found.

It splits a large file into fixed-size blocks, 128 megabytes by default in current versions, scatters those blocks over the machines of the cluster and keeps more than one copy of each block so that the failure of a machine does not lose data.

Virtualisation is the technique of running several logical machines on one physical machine and belongs to the chapter on cloud computing, not to the definition of big data.

On-Line Transaction Processing is the mode in which a bank counter, a railway booking window or a payment gateway works: each transaction is processed the moment it is entered, so the response to the user is immediate, and every committed transaction is written at once, so the database always reflects…

A data warehouse is exactly that, a central store into which data from many operational systems is extracted, cleaned and loaded so that it can be analysed for decision making.

The correct answer is A, Sir Mortimer Wheeler, who came as Director-General in 1944 and insisted that a mound be dug layer by layer, each layer recorded in section with its pottery, so that the order of occupation could be read from the earth itself; he applied the method at…

Appointed by Lord Curzon in 1902 and Director-General until 1928, he put Harappa and Mohenjo-daro in the hands of Daya Ram Sahni and R. D. Banerji, saw that the seals and bricks from the two places belonged to one unknown civilisation and announced it in 1924, afterwards publishing the great…

Travelling by train through Raisen district in Madhya Pradesh in 1957, he noticed the rock formations rising above the forest, returned to examine them and found hundreds of shelters whose walls carry paintings of hunters, dancers and animals running from the Upper Palaeolithic to historical times; Bhimbetka was added to…

Lothal lies in Ahmedabad district of Gujarat on the Bhogava, and the baked brick basin found there, connected to the river by a channel, is generally identified as a dockyard, which makes Lothal the port town of the Harappan world; it also yielded a bead factory, a warehouse and the…

The correct answer is B, Daya Ram Sahni, who was appointed in 1931, having already made his name by excavating Harappa ten years earlier.

The amendment of 2010 declared the belt of a hundred metres around every centrally protected monument or site a prohibited area, in which construction and mining are barred except for repairs to the monument itself, and the next two hundred metres a regulated area, where building needs the permission of…

It lets the central government declare a monument or an archaeological site to be of national importance, controls excavation and punishes damage, and its amendment of 2010 fixed the hundred metres around such a monument as a prohibited area and the next two hundred metres as a regulated area.

He found the Survey starved of money and nearly wound up, restored its budget, appointed John Marshall as Director-General in 1902 and carried the Ancient Monuments Preservation Act of 1904, the first law in India that let the government protect a monument and stop its owner from damaging or exporting…