STRUCTURED QUERY LANGUAGE(SQL) Created by: B Mokshagna Reddy (BMR) SQL DATA DEFINITION AND DATATYPES SQL Schema: An SQL schema is identified by a schema name and includes an authorization identifier name to indicate user or account who owns the schema, as well as descriptor for each elements in the schema. Schema creation with authorization: CREATE SCHEMA DATABASE_NAME AUTHORIZATION IDENTIFIER; Eg: CREATE SCHEMA COMPANY AUTHORIZATION ‘JSMITH’; Catalog: Named collection of schemas. Data Definition, Constraints, and Schema Changes Used to CREATE, DROP, and ALTER the descriptions of the tables (relations) of a database Creating a Database Syntax: CREATE DATABASE database_name; Creating a Table Syntax CREATE TABLE table_name (Column_name datatype[(size)], Column_name datatype[(size)], ); Specifies a new base relation by giving it a name, and specifying each of...
CHORDATA Created by: B Mokshagna Reddy (BMR) Introduction to Phylum - chordata ❖Chordates are animals characterized by the presence of notochord at some stage during their development. Members possess a hollow nerve cord and pharyngeal gill slits. The other general characteristic features of Chordates are as follows ❖They are bilaterally symmetrical, triploblastic, and coelomate with the organ-system level oforganization. ❖They hold a post-anal tail. ❖The body includes a closed circulatory system. ❖In some members of Phylum Chordata, the notochord is present only in the larval tail, and in some, it is present throughout their life from head to tail region. ❖Chordates have many sub-divisions and Protochordates are one of the earliest to evolve. ❖Three subphylums come under Chordata: 1. Urochordata– notochord present only in the larval tail, e.g. Ascidia, Salpa, Doliolum 2. Cephalochordata– notochord ...