Add db skills

PR-URL: #156

Author: tshemsedinov

README.md

@@ -7,6 +7,7 @@
 - [Asynchronous programming](Skills/Async.md)
 - [Node.js and Backend](Skills/NodeJS.md)
 - [Multi-paradigm programming](Skills/Paradigms.md)
+- [Databases](Skills/Databases.md)
 - [Architecture](Skills/Architecture.md)
 
 ## How to use

Skills/Databases.md

@@ -0,0 +1,94 @@
+## Databases
+
+- Theory and concepts
+  - Data types
+  - Performance tuning
+  - Migrations
+  - Schema versioning
+  - Backup and recovery
+  - Database scalability
+  - Relational databases
+  - Key-value store
+  - Tuple store
+  - Graph databases
+  - Object databases
+  - Column databases
+  - Navigational databases
+  - Hierarchical databases
+  - In-memory databases
+  - Inverted index
+  - Data control language (DCL)
+  - Data definition language (DDL)
+  - Data manipulation language (DML)
+  - Data query language (DQL)
+- Relational
+  - Entity-Relationship Diagram
+  - Normal forms
+  - Indexing
+  - Promary keys
+  - Foreign keys
+  - Transactions
+  - Views
+  - Subqueries
+  - Stored procedures
+  - SQL functions
+  - Materialized views
+  - Replications
+  - Virtualization
+- SQL
+  - `SELECT`
+  - `INSERT`
+  - `UPDATE`
+  - `DELETE`
+  - `LIMIT`
+  - `OFFSET`
+  - `ORDER BY`
+  - `GROUP BY`
+  - `HAVING`
+  - `EXISTS`
+  - `JOIN`
+  - `INNER JOIN`
+  - `LEFT JOIN`
+  - `RIGHT JOIN`
+  - `UNION`
+  - `DISTINCT`
+  - `WHERE`
+  - `LIKE`
+  - `IN`
+  - `BETWEEN`
+  - `CREATE TABLE`
+  - `ALTER TABLE`
+  - `DROP TABLE`
+  - `PRIMARY KEY`
+  - `FOREIGN KEY`
+  - `CHECK`
+  - `DEFAULT`
+  - `INDEX`
+  - `UNIQUE`
+  - `GRANT`
+  - `REVOKE`
+  - `DENY`
+  - `EXPLAIN`
+- Engines
+  - PostgreSQL
+  - Oracle
+  - MySQL
+  - MariaDB
+  - MS SQL Server
+  - Redis
+  - Rabbit
+  - MongoDB
+  - Memcached
+  - Riak
+  - DB2
+  - SQLite
+  - DynamoDB
+  - Firebase
+- Data engineering
+  - Data warehousing
+  - Business intelligence
+  - Big data
+  - Data analysis
+  - AI tools
+  - Cloud databses
+  - Data Visualization