Data Flashcards
selection operation
takes rows from one table and creates a new table
SELECT statement
identifies the records from a query/request
FROM statement
identifies the table name
WHERE statement
Defines the condition from query/request
union operation
combines fields from multiple tables with same attributes and data types
product operation
creates a table that includes the attributes from two tables
join operation
combines two tables appends matching search criterion within new table
Graph stores
Stores information about networks of data (such as social connections)
Wide-column stores
A type of NoSQL db that uses column families that store columns of data together
-optimized for queries on large data sets
What is a Document-format database?
A db that pair each key with a document (complex data structure that can contain many different key-value pairs)
NoSQL database
“Not Only SQL” a db that can accommodate a variety of data models (key-value, document, columnar, and graph formats
-data is placed in tables designed before the database is built
- useful for working with large sets of distributed data
What is a Cloud databases and the benefits it offers?
Databases that are optimized to work in a cloud environment
practical benefits:
-Flexible to increase resources
-Highly availability
-Support SaaS cloud deployments
Data Lake
is a system of data stored in raw format, and can include both structured data, such as tables, and unstructured data, such as audio and video recordings
- usually a single store of all enterprise data as well as information derived from data during reporting, transactions, or other activities
Distributed Databases
consists of data residing on different machines
