I wanted to discuss an SQL statement with you, really break down the anatomy of an SQL statement. As long as you understand the components of an SQL statement, building one and remembering which pieces of the puzzle are required at what time is going to become quite simple. Trust me when I tell you this, after x amount of practice, you know what I mean by x amount. After a certain number of times that you have written an SQL statement, it will make perfect sense. Let's get started here, INSERT, UPDATE, and DELETE are actions. These are part of the DML statement. DML is data manipulation language. The reason it's referred to as a DML is because all three of these, INSERT, UPDATE, and DELETE are manipulating the data, makes sense, doesn't it? So first, think about that INSERT, UPDATE, and DELETE. These are the beginning of a SQL statement. And when I say the beginning of an SQL statement, you start the SQL statement with an INSERT, meaning you want to add a new row in a table. If you start the SQL statement with an UPDATE, it means you want to modify or change the data in a table. And if you decide to start the SQL statement with a DELETE, it would mean that you want to remove data from a table. So you would do one of the three. When you insert data, it simply means that you want to add rows in a table. A table consists of multiple columns, you know that. It consists of perhaps an ID column, perhaps some kind of a name column, maybe some type of a description column. An INSERT statement will let you add data to these columns. And the combination of these columns makes a row. Each row in this particular instance would contain a ID, a name, and a description. Each row would contain, in this case, these three columns. So if you wanted to add a new row in a table like that, you would use a INSERT statement. At the same time if you had ID and name columns, and you wanted to manipulate one of these rows. And you wanted to manipulate one of these particular columns in a row. You would issue a UPDATE. You want to change a data in an existing column. So for example maybe for ID 3 you want to change C to a D. That would require an UPDATE statement. Then there is the DELETE statement. DELETE statement lets you remove row from a table. If you wanted to remove the second row altogether, you would issue a DELETE statement. So INSERT adds rows, UPDATE modifies data in a row or rows, and DELETE will let you remove a row or multiple rows from an existing table. In addition to inserting, updating, or deleting data, you might want to select data or retrieve data from an existing table. SELECT, the actual clause SELECT, INSERT is a clause, UPDATE clause, DELETE clause, and there's a SELECT clause. SELECT clause lets you return data from a table. So if you had rows in a table, you would use a SELECT statement to bring data back. If you wanted to find out what the rows contained, what products were listed, what the descriptions of those products were, what the price of particular products were, you would use a SELECT statement to accomplish that task. The FROM clause combined with the SELECT clause, would allow you to specify which table or tables you want to retrieve data from. The FROM clause goes in conjunction with the SELECT clause and is required. Then there is a optional WHERE clause. WHERE clause lets you filter the data that you want to return. So you could say that you want to select a particular product from the products table, and the product you're looking for has the product ID of 3. So that would be the SELECT statement retrieving the data. The FROM clause allowing you to specify which table the data is going to come from. And then the WHERE clause letting you specify how you want to filter the data exactly the pieces that are needed. INSERT, UPDATE, DELETE the SELECT statement, the FROM clause and the WHERE clauses, these are the basic components that make up the anatomy of an SQL statement.
