What is the purpose of a schema?
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You can think of it as another logical layer that groups objects inside of a database. So tables, views, functions etc. logically don't belong to the database directly, but to a schema, so you can have objects with the same names in different schemas within a database. Even if you don't create or specify a schema yourself, most databases revert to a "default" schema that is created with the database ("public" for PostgreSQL or "dbo" for SQL Server). Show Users, however, are usually created on the database level (they are "owned" by the database whereas e.g. tables are "owned" by the schema), so you can also use schemas to orgnanize access to objects between users by giving users permissions on some schemas and not others. Recent Interview Questions | Search | Subscribe (RSS) INTERVIEW QUESTION: ANSWERAn XML Schema is a document that is itself described using XML and which defines how an XML document must be structured in order to conform to structured required by the a system or service which references the XML Schema. Specifically it defines:
The term DTD (Document Type Definition) is often used when discussing the acceptable form of XML documents. However, XML Schemas are successors to XML DTDs and have a number of benefits over DTDs. Some of these benefits are:
XML schemas are able to enforce specific rules and data conformity such as:
Sample XML which conforms to Schema
ADDITIONAL ANSWERS / COMMENTSOnly registered users may post comments. What is the purpose of schema in database?A database schema defines how data is organized within a relational database; this is inclusive of logical constraints such as, table names, fields, data types, and the relationships between these entities.
What is the main idea of schema?Schema is the technical term used by cognitive scientists to describe how people process, organize, and store information in their heads. Schemas, or schemata, are seen as cognitive constructs by which we organize information in our long-term memory (Widdowson, 1983).
What are the benefits of schemas?The primary benefit of Schema Therapy is its ability to 1) help people identify and adjust their negative patterns of behaviour and 2) learn how to ensure their emotional needs are met, in a healthy way. There are four elements to the Schema Therapy model: emotional needs, schemas, coping styles and modes.
What is a schema and why do we have them?Schema is a mental structure to help us understand how things work. It has to do with how we organize knowledge. As we take in new information, we connect it to other things we know, believe, or have experienced. And those connections form a sort of structure in the brain.
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