Railway GK Questions 2026

The year 2019 marked one hundred and fifty years since Dmitri Mendeleev arranged the elements in his table in 1869, and the United Nations declared it the International Year of the Periodic Table alongside the International Year of Indigenous Languages.

The year 2016 was the International Year of Pulses, led by the Food and Agriculture Organization, and it drew attention to crops such as gram, arhar, moong, urad and masoor, which give protein cheaply and fix nitrogen in the soil.

The General Assembly declared 2020 the International Year of Plant Health to show how protecting plants from pests and diseases protects food supply, trade and the environment, and the Food and Agriculture Organization led the year.

The year 2024 was the International Year of Camelids, the family of animals that includes camels, llamas, alpacas, vicunas and guanacos, which carry loads, give milk, meat and wool, and support families in deserts and high mountains where little else can live.

An international year exists because the Assembly, in which every member state has one vote, adopts a resolution declaring it, usually on a proposal from one or more states.

India moved the proposal, it was supported by more than seventy member states, the General Assembly adopted it in 2021 and the year was observed in 2023 with the Food and Agriculture Organization as the lead agency.

The United Nations General Assembly declared 2023 the International Year of Millets on a proposal moved by India and supported by more than seventy countries, and the Food and Agriculture Organization led the observance; India promoted the crops at home under the name Shree Anna.

The Data Control Language governs who may do what inside the database: GRANT gives a user a privilege such as the right to read or to update a table, and REVOKE withdraws a privilege already given.

MongoDB stores data as documents in a flexible, JSON-like form instead of as rows in tables with a fixed set of columns, and it is queried through its own interface rather than mainly through SQL, which makes it the standard example of a NoSQL database in exam papers.

A table is in second normal form when it is already in first normal form and no non-key attribute depends on only a part of a composite primary key; such a partial dependency is removed by moving that attribute into a table of its own.

The degree of a relation counts its attributes, that is its columns, so a student table holding roll number, name, class and marks has degree four whatever the number of students in it.

Isolation means that transactions running at the same time do not see one another's incomplete work, so two clerks booking the last seat cannot both succeed; the database behaves as though the transactions ran one after the other.

A foreign key is the column that stores values belonging to the primary key of another table, so a marks table can carry the roll number of a student table and the two tables can then be joined; the database uses it to enforce referential integrity, refusing a value that…

The designer picks one candidate key as the primary key of a table, and the database then enforces two rules on it: its value must be different in every row, and it can never be left null, since a missing value would make a row impossible to identify.

TRUNCATE empties a table in one operation, leaving the columns, data types and constraints in place so that the table can be filled again at once; because it changes the object rather than selected rows it is grouped with the Data Definition Language and it is much faster than deleting…

The Data Definition Language deals with the structure of the database rather than with the data inside it, and CREATE is its basic command, used to build a table, a view or the database itself; ALTER, DROP, TRUNCATE and RENAME belong to the same group.

In the vocabulary of the relational model a table is a relation, and one complete horizontal entry of that table, such as all the details of a single student, is a tuple; the ordinary words for it are row and record.

Codd, a British computer scientist working at IBM, set out the relational model in a paper published in 1970, proposing that all data be held in simple two-dimensional tables and joined by matching values rather than by fixed pointers.

The hierarchical model is the first data model used in commercial database software; IBM built its Information Management System on it in the 1960s for the Apollo programme.

The Light We Carry is her second book, written after the memoir Becoming, and it sets out the habits and ideas she uses to face uncertainty.