More and more people are getting into web designing, yet many are put off by SQL for reasons which I don't understand. I assure you it is very easy, in this tutorial I'll try to introduce you to the extreme basics of the structured query language.
In an SQL database there can be many tables, these tables store the data that you want to get at, let's have a look at an example of a simple table. Table: People
Above we have a representation of a table in an SQL database. You can see why they are named tables. They have rows and columns, each row is a separate line in the database, and each column represents a data group for the table. We can use SQL to retrieve selective data, update and change data, delete data... etc. from this table.
Note that the above table is named people, let's have a look at a very simple SELECT statement:
That's it, read it. Select name from, we are telling SQL to select the name column from the people table, what would this select?
Bob, Jill, Joe, Jeff, Sue
Simple enough right? We can select more than one column:
This would select the name column and the gender column, what would this select?
Bob, male, Jill, female, Joe, male, Jeff, male, Sue, female
There is a short-hand way to select all of the columns:
The * means select all columns (id, name, gender, location and age).
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