Questions

The relationship between a cathode and an anode involves the transfer of electric charge between them. The cathode is the negative terminal on the battery, which has zero electric potential. The anode is the positive terminal on the battery and has the battery's maximum electric potential. Current flows from the battery's anode (positive terminal) to the cathode (negative terminal). In electron flow, electrons leave the negative side of the battery and move towards the positive side of the battery.

Hence, The relationship between a cathode and an anode involves Electrons.

The reactivity of an atom arises from the existence of unpaired electrons in the valence shell.

SQL statements are broadly classified into three. They are

1. DDL – Data Definition Language

DDL is used to define the structure that holds the data. For example, Create, Alter, Drop and Truncate table.

2. DML – Data Manipulation Language

DML is used for manipulation of the data itself. Typical operations are Insert, Delete, Update and retrieving the data from the table. The Select statement is considered as a limited version of the DML, since it can't change the data in the database. But it can perform operations on data retrieved from the DBMS, before the results are returned to the calling function.

3. DCL – Data Control Language

DCL is used to control the visibility of data like granting database access and set privileges to create tables, etc. Example - Grant, Revoke access permission to the user to access data in the database.