Remember to

• Remind students to install Firefox.

Walk students through installing SQLite Manager Add-on.

Why use a database management system

• Simple and effective software for storing, managing and retrieving information
• Widely used to store and maintain lots of existing data
• Fast processing across large amounts of data
  • Out-of-memory and remote processing for really large data
  • Can handle spatially explicit queries (GIS)
• Improve quality control of data entry
  • Set valid data type and value constraints.
  • Use data entry forms in Excel, Access, Filemaker, etc.
  • Use quality control scripts to test entered data.
• Concepts are core to understanding data manipulation in other languages

Relational databases

• We will be working with ‘Relational Databases’.
  • Data is stored in tables.
    • One table per type of data
      • Tables can be linked together to combine information.
    • Each row contains a single record.
      • A single observation or data point
    • Each column or field contains a single attribute.
      • A single type of information
  • The concepts of relational database management are core to understanding how to do similar things using programming languages such as R or Python.
• We will primarily use SQLite.
  • Simple to use
  • Almost no work to set up
  • Stored in single file
  • But, there are lots of alternatives
  • Access - commonly used, GUI
  • PostgreSQL - fast/powerful, lots of users

Importing table into SQLite Manager

1. Download the Portal Project survey data
2. Open SQLite Manager
3. Database -> New Database -> name portal_mammals -> OK -> Open (don’t select any files)
4. Import button or Database -> Import
5. Select File -> navigate to just downloaded surveys.csv -> Open
6. Check First row contains column names & select Comma option
7. OK to modify the data
8. Name table surveys

9. Select data types

   • Fields in databases have types that define the kind of data they contain.
   • Each field/column can only have one type.
   • We have to define the types in advance.
   • Types include
     • Integer
     • Text (varchar)
     • Decimal/Double/Real/Float
   • Types are highly configurable for when space is limiting
     • Maximum value of integers
     • Maximum length of text
     • How many values before and after the decimal place

10. Select record_id as the Primary Key and click OK.

    • Every table “needs” a column (or set of columns) that is unique across records/row.
    • This is called the Primary Key.
    • The easiest way to do this is to use an INTEGER that increments every time a new record is added.
    • Many databases that you import will already have a field like this.
    • Otherwise autogenerates one.

Show students the

• objects panel with Tables and Views.
• Browse & Search tab.
• Structure tab.

We’ve just done most of Exercise 3. Do Exercise 3.11 - Importing Data.