zoqaaware.blogg.se - Coding with khan academy

I always wonder what made it different that last time, and if it applies to others. I bounced off each time, until finally sticking.

Databases can import from and export to spreadsheets.I've done a lot of pondering about how to teach programming because I tried to learn several times myself, both on my own and in classes.

Databases are good at working with information that repeats.

Databases are more efficient at storing relationships among things you’ve already entered.

They can’t extract selected information from records into a new display.

Spreadsheets are good for sorting entire records.

Spreadsheets are good for smaller lists, say under 100 items.

Forms, reports and queries all draw information from data in an entire database. Reports are a way to retrieve information and are usually intended for printing.Ī query is a search for information across an entire database. A form allows easy display and entry of information on a monitor. (See below for an example.)īesides tables, a relational database will also have forms.

Some tables will contain only ID numbers that match items in other tables, effectively storing the relationship among those things. Instead of entering "Seattle" or "Las Vegas" into the main table, only an ID number is needed. For example, a relational database for an address book could have a table for city names. It has only one table of information.Ī relational database has several tables for efficient storage of information because the information can be reused, needing only an ID number to represent data. A database like this is called a flat file. All the information about one person is a record. In an address book, the state is a field. An address book is an everyday database with a single table of information. A database is a collection of data on a computer organized for easy entry, searching and retrieval.