SQL DataTypes

Data Types:In SQL (Structured Query Language), a datatype specifies the type of data that can be stored in a column of a table. It defines the kind of values that a column can hold, such as integers, strings, dates, etc. Each column in a table must have a specific datatype, which helps the database management system (DBMS) understand how to store, validate, and manipulate the data.

1. CHAR:

   • Stores fixed-size character data.

   • Capacity: Up to 255 characters.

   • Example: CHAR(10)

   • Note: Wastes space if not fully utilized.

2. VARCHAR:

   • Stores variable-length character data and accepts alphanumeric values.

   • Capacity varies depending on the database.

   • Example: VARCHAR(10)

   • Efficient use of storage as it only uses what's needed.

3. VARCHAR2:

   • Similar to VARCHAR, used in Oracle databases.

   • Capacity: Up to 2000 characters.

   • Example: VARCHAR2(10)

   • Efficient use of storage, eliminates non-padded information.

4. NUMBER(p, s):

   • Represents fixed-point numbers with precision (p) and scale (s).

   • Example: NUMBER(5, 2) for numbers like 123.45.

   • Can store up to 36 digits without precision and scale.

5. DATE:

   • Represents date and time.

   • Standard format: DD-MM-YY.

6. LONG:

   • Used for storing large data (up to 2GB) in a column.

7. RAW (or Long Raw):

   • Used for storing binary data, like images.