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Relational database models

• The structure of a relational database
• Relational operators

Download the data

• Rules for writing SQL queries
• The syntax for the SELECT
• Selecting all columns
• Inquiries from arithmetic operations
• Aliases columns
• Literals
• Concatenation

Restrict results

• The WHERE clause
• The comparison operators.
• LIKE Condition
• Prerequisite BETWEEN ... AND
• IS NULL condition
• IN condition.
• Logical operators
• Many of the conditions in the WHERE clause
• The order of operators
• DISTINCT clause

Sorting Data

• The ORDER BY clause
• Sorting by multiple columns or expressions

SQL Functions

• The differences between the functions of single and multi-rows
• Functions text, numeric, date,
• Conversion functions
• Nesting functions
• Handling of NULL values

Aggregating data using the grouping function

• Grouping functions
• How grouping functions treat NULL values
• Create groups of data - the GROUP BY clause
• Grouping multiple columns
• Reducing the function result grouping - the HAVING clause

Retrieving data from multiple tables

• Types of joins
• Aliases tables
• Joins in the WHERE clause
• INNER JOIN Inner join
• External Merge LEFT, RIGHT
• Cartesian product

Subqueries

• Place subqueries in the SELECT command
• Subqueries single and multi-lineage
• Operators Subqueries single-line
• Operators Subqueries multi-IN, ALL, ANY

Collective operators

• UNION operator
• INTERSECT operator
• EXCEPT operator

Insert, update, and delete data

• INSERT command
• UPDATE command
• DELETE command

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