SQL > SQL Tutorial Videos > Table Management Video

This video discusses how to manage tables in a relational database. The commands covered are CREATE TABLE, DROP TABLE, and TRUNCATE TABLE. After you finish watching this video, you'll be able to perform basic table management in a relational database.

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Video Transcription

In this tutorial, we look at how to use SQL to manage database tables. Before we dive into the specific commands, let us first go through the basics of a relational database.

In a relational database, data is stored in tables. Each table has a table name. A table consists of columns and rows. Each column is a field in a record, and there is a column name associated with each column. Each row represents one record. Usually when we say how many records we have, we are referring to the number of rows. With this information, now we are ready to look at how to use SQL to manage database tables.

The first thing we need to do before we can store any data in a relational database is to create a table that can store data. The SQL command for this is CREATE TABLE. The syntax for CREATE TABLE is

CREATE TABLE "table_name"
("column 1" "data_type_for_column_1",
"column 2" "data_type_for_column_2"
... )

Different databases have different data types. But by and large, the common data types are numeric, character string, date/datetime, and binary.

For example, if we issue the following SQL command,

(Last_Name CHAR(20),
First_Name CHAR(20));

we will have created a table in the database called USER_TABLE, which has two columns: Last_Name and First_Name, both being 20 characters long. Upon creation, this table holds no data.

In order to manage the database effectively, we will also need to have the ability to remove tables from a database. The SQL statement to do this is DROP TABLE. The syntax for DROP TABLE is simply

DROP TABLE "table_name";

Dropping a table removes the table from the database. All data stored in that table is also gone.

To remove the table we had created, we issue the following SQL statement:


Sometimes we will only want to remove the data from a table, while keeping the table structure. The SQL command for this is TRUNCATE TABLE. The syntax for TRUNCATE TABLE is

TRUNCATE TABLE "table_name";

Once this command is executed, the table will be empty. The table itself still exists in the database and can be used if needed.

To truncate the table we had created, we issue the following SQL statement:


List of SQL Video Tutorials

 Title  Description 
 SQL Basics Tutorial Video  How to use SQL to retrieve data from a relational database. 
 Union, Intersect, Minus Video  How to combine two sets of results using SQL. 
 Table Management Video  How to manage database tables in SQL. 
 Table Constraint Video  How to enforce constraints on a column using SQL. 
 Database View Video  What is a database view and how to use it. 

This page was last updated on June 19, 2023.

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