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Character
Subtype Width Valid examples Invalid examples
CHAR(L) or CHARACTER(L) L For type CHAR(10) For type CHAR(10)
Fixed-length character
strings of length L. 'IIIT Delhi' is stored as 'IIIT 110016
Delhi' 29-01-2022
'IIT' is stored as 'IIT ' Note: both the above
examples are not a string
Note: in both of the above examples, the
number of bytes required to store the
data is 10 bytes.
VARCHAR(L) <=L 'IIIT Delhi' is stored as 'IIIT For type CHAR(10)
Variable-length character Delhi'
strings of length upto L.
110016
'IIT' is stored as 'IIT' 29-01-2022
Note that, each string above require one Note: both the above
byte more than the length of the string. examples are not a string
Therefore, the string 'IIIT Delhi'
will need 11 bytes, whereas 'IIT' need
4 bytes in memory.
DATE
DATE: The standard date format is YYYY-MM-DD.
The data type DATE denotes a date. The standard date format is YYYY-MM-DD. However, SQL also permits other
formats like DD-MM-YYYY for storing and retrieving dates.
TIME: The data type TIME denotes time. It supports various time formats such as HH:MM: SS, HH-MM-SS, HH.MM
AM/PM.
4.4 SQL Statements and Functions
This section will discuss several SQL statements and functions for defining and manipulating data. Each SQL statement
terminates with a semicolon.
4.4.1 CREATE DATABASE statement
Creating a database is the first step in database management. CREATE DATABASE statement creates a database. The
syntax for the CREATE DATABASE statement is as follows:
CREATE DATABASE database_name;
134 Touchpad Informatics Practices-XII

