The CREATE TABLE
statement is used to create a new table in a database.
CREATE TABLE
table_name (
column1 datatype,
column2 datatype,
column3 datatype,
....
);
The column parameters specify the names of the columns of the table.
The datatype parameter specifies the type of data the column can hold (e.g. varchar, integer, date, etc.).
Tip: For an overview of the available data types, go to our complete Data Types Reference.
The following example creates a table called "Persons" that contains five columns: PersonID, LastName, FirstName, Address, and City:
CREATE TABLE Persons (
PersonID int,
LastName varchar(255),
FirstName varchar(255),
Address varchar(255),
City varchar(255)
);
The PersonID column is of type int and will hold an integer.
The LastName, FirstName, Address, and City columns are of type varchar and will hold characters, and the maximum length for these fields is 255 characters.
The empty "Persons" table will now look like this:
PersonID | LastName | FirstName | Address | City |
---|---|---|---|---|
Tip: The empty "Persons" table can now be filled with data with the SQL INSERT INTO statement.
A copy of an existing table can also be created using CREATE TABLE
.
The new table gets the same column definitions. All columns or specific columns can be selected.
If you create a new table using an existing table, the new table will be filled with the existing values from the old table.
CREATE TABLE
new_table_name AS
SELECT
column1, column2,...
FROM
existing_table_name
WHERE ....;
The following SQL creates a new table called "TestTables" (which is a copy of the "Customers" table):
CREATE TABLE TestTable AS
SELECT customername, contactname
FROM customers;
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