What is a table?

by | Apr 8, 2021 | Databases

What is a table?
A table is an object that holds things. For example, a kitchen table hold things like plates, cups, and other things we use to eat our food.

What is a database table?
A database table also holds things. A database table holds data.

How is the data organized in a database table?
The data is organized into records and fields. Records are like rows in a spreadsheet, fields are like the columns in a spreadsheet. The table itself is like a sheet in Excel.

Do the fields have names?
Yes. Each field in the table must have a unique name. It is a best practice to not include spaces in a field name.

Do the rows have names?
No. But a good designer will usually designate one field to have a unique value. This one field is called a primary key. You can therefore refer to a row by the unique value in the primary key field.

Are there any special rules for how the data is entered into the fields?
Yes. The database designer gets to decide what the rules are. Specifically, the designer should specify a data type, which defines the type of data (number, date, text, etc.) that can be entered into the field.

How many tables can I have in a database?
That depends on the type of database. A Microsoft Access database can have up to 2,048 tables, while a SQL Server database, in theory, can have 2,147,483,647 tables. In practical terms, you will normally have nothing near that many tables.

This blog post has discussed the basics of tables in a database. A future blog post will discuss how the tables in a database are related to each other.  If you would like to learn more about how TechMentors can help your business, please contact us.