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• Relational database models
  Relational operators
  Characteristics of declarative SQL language
  SQL syntax
  Division language DQL, DML, DDL, DCL
  Data Query Language
  SELECT queries.
  Aliases columns of tables
  Service date (DATE types, display functions, formatting)
  Group Features
  Combining internal and external tables (JOIN clause)
  UNION operator
  Nested Subqueries (the WHERE clause, the table name, column name)
  Correlated subqueries
  Data Modification Language
  Inserting rows (INSERT clause)
  Inserting rows by request
  Variation of the rows (UPDATE)
  Delete rows (DELETE)
  Data Definition Language
  Creating, altering and dropping objects (CREATE, ALTER, DROP)
  Creating tables using subquery (CREATE TABLE .... AS SELECT...)
  CONSTRAINTS
  Options NULL and NOT NULL
  CONSTRAINT clause
  ENUM type
  type SET
  PRIMARY KEY condition
  UNIQUE condition
  FOREIGN KEY condition
  DEFAULT clause
  Transactions
  The command COMMIT, ROLLBACK, SAVEPOINT