The CREATE
TABLE statement is one of the data definition language (DDL)
statements. DDL are SQL statements used to create, modify, or remove database
structures. To create a
table, a user must have the CREATE TABLE rights and
sufficient storage in which user can create objects.
Syntax
CREATE
TABLE [schema.]table
(column
datatype [DEFAULT expr][, ...]);
Options
schema
|
Is
the same as the owner’s name
|
table
|
Is
the name of the table
|
DEFAULT
expr
|
Specifies
a default value if a value is omitted in the INSERT statement
|
column
|
Is
the name of the column
|
datatype
|
Is
the column’s data type and length
|
When the table
is not present in the DB it will throw error message as shown below.
Example
Let us create table
students having First name, Last name, Roll no, Address and City column.
CREATE TABLE
students
(
FirstName varchar(255),
LastName varchar(255),
RollNo int,
Address varchar(255),
City varchar(255)
);
Now when the
table is created we can show all the records of table by select statement as
shown below:
select * from
students
As we have not
inserted any records in the table, hence no rows are reported.
TAB and COL
We have tab to
show all the tables currently present in the database.
Also we have col
to search for specific table name when we only know column name for reference.
This two are
very useful for finding tables in day to day operations.
select * from
tab
where tname = 'STUDENTS'
select * from
col
where cname = 'FIRSTNAME'
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