9.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

Rows can be removed from a table using the DELETE command. Suppose you are no longer interested in the weather of Hayward. Then you can do the

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5.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

To retrieve data from a table, the table is queried. An SQL SELECT statement is used

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1.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

This chapter provides an overview of how to use SQL to perform simple operations. This tutorial is only intended to give you an introduction

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8.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

You can update existing rows using the UPDATE command. Suppose you discover the temperature readings are all off by 2 degrees after November 28

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7.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

Like most other relational database products, PostgreSQL supports aggregate functions. An aggregate function computes

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6.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

Thus far, our queries have only accessed one table at a time. Queries can access multiple tables at once, or access the same table in such a way that multiple rows of the table

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4.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

The INSERT statement is used to populate a table with rows:

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3.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

You can create a new table by specifying the table name, along with all column names and their types:

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2.
  • References/Database/PostgreSQL/Tutorial/The SQL Language

PostgreSQL is a relational database management system (RDBMS). That means it is

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