Therefore, it is important that every single record in a database has something to uniquely identify it and this is called the 'Primary Key' or sometimes the 'Key Field'. When you started school, you were given a 'student ID' or an 'office number' (primary key).
Ignoring any maintenance costs, asphalt is generally much cheaper to install than concrete. On average, the cost per square foot for asphalt will run between $2.50 to $4.00. Fluctuations in crude oil prices can cause fluctuations in asphalt prices but the price will remain around this range. Concrete, on the other hand, can run between $4.00 to $6.00 per square foot for basic installation and can cost more depending on different finishes and detail. Itâs not unheard of to have a stained concrete driveway with a smooth finish cost over $15.00 per square foot.
1 On average, getting concrete floors can cost anywhere from as little as $2 to as much as $17 per square foot. 2  An economical option, which can just change the tone of the concrete floor, will typically cost less than $6. ConcreteNetwork.com provided an overview on what most concrete flooring jobs would cost. 2  They noted that the average can be anywhere from $2.50 to as much as $30 per square foot.