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Bubli Sagar
Schema
A database of information that be accessed by many individuals or a network for the use of editing, creating, and manipulating data and information. In GIS, an enterprise database schema is used to distribute and maintain geographic data in the same way.
In a relational database, the schema defines the tables, the fields in each table, and the relationships between fields and tables.
secret...know it yourself
A database schema is described in a formal language supported by the database management system (DBMS). In a relational database, the schema defines the tables, the fields in each table, and the relationships between fields and tables. Schemas are generally stored in a data dictionary. Although a schema is defined in text database language, the term is often used to refer to a graphical depiction of the database structure Levels of database schema 1. Conceptual schema, a map of concepts and their relationships 2. Logical schema, a map of entities and their attributes and relations 3. Physical schema, a particular implementation of a logical schema 4. Schema object, Oracle database object 5. Schema is the over all structure of the database
A relational schema is a structure that represents the logical view or design of a database. It defines how the data is organized and the relationships between different entities or tables. It typically includes the names of the tables, their attributes or columns, and the constraints that define the relationships between them.
Relational Schema refers to meta-data elements which are used to describe structures and constraints of data representing a particular http://wiki.answers.com/Describe_the_differences_in_meaning_between_the_terms_relation_and_relation_schema#. Whereas a relation is a property or predicate that ranges over more than one argumentHere's some translation from "Relational Algebra" to http://wiki.answers.com/Describe_the_differences_in_meaning_between_the_terms_relation_and_relation_schema#terminology:"Relation" = Table."Relation Schema" = Table definition.So for example, the "schema" for the Person "relation" is: Person(FirstName, LastName, Age, Gender, Address)Also in relational Algebra, a "tuple" is a table row, and an "attribute" is a table column.
The properties of a database are commonly called a schema. The schema describes the tables in the database, the fields inside each table, the contents of each field, etc.
The schema (pronounced skee-ma) of a database system is its structure described in a formal language supported by the database management system (DBMS). In a relational database, the schema defines the tables, the fields, relationships, views, indexes, packages, procedures, functions, queues, triggers, types, sequences, materialized views, synonyms, database links, directories, Java, XML schema's and other elements.Schema's are generally stored in a data dictionary. Although a schema is defined in text database language, the term is often used to refer to a graphical depiction of the database structure.Hope this helps!Inclus - We provide indivdual and coporate trainingsEducate, Learn & Servewww.Inclus.net
external schema
Relational Schema refers to meta-data elements which are used to describe structures and constraints of data representing a particular domain. Whereas a relation is a property or predicate that ranges over more than one argument Here's some translation from "Relational Algebra" to SQL terminology: * "Relation" = Table. * "Relation Schema" = Table definition. So for example, the "schema" for the Person "relation" is: Person(FirstName, LastName, Age, Gender, Address) Also in relational Algebra, a "tuple" is a table row, and an "attribute" is a table column.Mathematician define a relation to be subset of cartesian product list of domains.In daabase relation is a set of entities with similar attributes.In other way we can consider a relation as a table and it's rows as entities, and table's columns as attributes.Concept of relation corresponds to programming language notion of variable.relational Schema corresponds to the programming language notion of type definition.It is the logical design of database.e.g. for a relation account having attributes account_number, branch_name and balance, relational schema is specified as -Account_schema= (account_number, branch_name, balance)
To create tables in any schema in a relational database, you typically use the SQL CREATE TABLE statement, specifying the schema name followed by the table name (e.g., CREATE TABLE schema_name.table_name). You also need to define the columns and their data types within parentheses. Ensure you have the necessary permissions to create tables in the specified schema. Lastly, you can include constraints such as primary keys or foreign keys as part of the table definition.
The semistructured model in advanced database management systems (ADBMS) allows for data to be stored without a strict schema like in relational databases. It provides flexibility in storing various types of data, allowing for different structures within the same database. This model is commonly used for data that does not conform to a fixed schema or where the schema may evolve over time.
It is called a schema.