Select ,Update ,Delete and Drop statement

Selecting data in SQL

Before everything we need to talk about SQL query process

The SQL SELECT Statement

The SELECT statement is used to select data from a database.

The data returned is stored in a result table, called the result-set.

There are several ways to select data from a Data base

Now we got data with famous baseball players!


Or you can mention the columns

Or the columns that you don't want ..for example, I am not interested in last names

WE added a couple of players for an example...we will execute it and refresh the Customer DB

The SQL WHERE Clause

The WHERE clause is used to filter records.

The WHERE clause is used to extract only those records that fulfill a specified condition.

Now without the " ' "..But Alex is a string , not a column

Now we will specify Mike Piazza

If we highlight the top

The SQL UPDATE Statement

The UPDATE statement is used to modify the existing records in a table.

We will update the new age of Alex Rodriguez

We can see the results after we double check the customer table

We can delete as well the DATA of the table with the delete Command

The SQL DELETE Statement

The DELETE statement is used to delete existing records in a table.

We see the results

When we want to Delete the whole table we will use Drop table command

The SQL DROP DATABASE Statement

The DROP DATABASE statement is used to drop an existing SQL database.

Now we will select our Customer table to see it..

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