Hello Dev, in today’s article we will be discussing the topic of SQL Server numeric data types. If you are a developer who is working with SQL Server, you must be familiar with numeric data types. These data types are used to store numerical data such as integers, decimals, and floating-point numbers. In this article, we will explore the different types of numeric data available in SQL Server and how to use them effectively.
What Are SQL Server Numeric Data Types?
SQL Server provides a wide range of numeric data types that can be used to store different types of numerical data. These data types are designed to handle different ranges of values and precision levels. Here are some of the most common numeric data types in SQL Server:
Numeric Data Type |
Description |
|---|---|
tinyint |
Used to store small integer values |
smallint |
Used to store medium-sized integer values |
int |
Used to store large integer values |
bigint |
Used to store very large integer values |
decimal |
Used to store fixed-point decimal values |
numeric |
Used to store fixed-point decimal values |
float |
Used to store floating-point decimal values |
real |
Used to store single-precision floating-point decimal values |
Understanding Integer Data Types
Integer data types are used to store whole number values. These values can be positive, negative, or zero. SQL Server provides four different integer data types: tinyint, smallint, int, and bigint.
Tinyint
The tinyint data type is used to store small integer values ranging from 0 to 255. This data type takes up only 1 byte of storage space and is useful when you need to store small integer values efficiently. Here is an example of how to define a column with the tinyint data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Age tinyint NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Age. The Age column is defined as a tinyint data type, which means it can store integer values from 0 to 255.
Smallint
The smallint data type is used to store medium-sized integer values ranging from -32,768 to 32,767. This data type takes up 2 bytes of storage space and is useful when you need to store larger integer values than the tinyint data type can handle. Here is an example of how to define a column with the smallint data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Age smallint NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Age. The Age column is defined as a smallint data type, which means it can store integer values from -32,768 to 32,767.
Int
The int data type is used to store large integer values ranging from -2,147,483,648 to 2,147,483,647. This data type takes up 4 bytes of storage space and is useful when you need to store even larger integer values than the smallint data type can handle. Here is an example of how to define a column with the int data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Age int NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Age. The Age column is defined as an int data type, which means it can store integer values from -2,147,483,648 to 2,147,483,647.
Bigint
The bigint data type is used to store very large integer values ranging from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. This data type takes up 8 bytes of storage space and is useful when you need to store very large integer values. Here is an example of how to define a column with the bigint data type:
CREATE TABLE Employee (Id bigint IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Age bigint NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Age. The Age column is defined as a bigint data type, which means it can store integer values from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.
Understanding Decimal Data Types
Decimal data types are used to store fixed-point decimal values. These values are useful when you need to store decimal numbers with a fixed number of decimal places. SQL Server provides two different decimal data types: decimal and numeric.
Decimal
The decimal data type is used to store fixed-point decimal values ranging from -10^38 +1 to 10^38 -1. This data type takes up 5 to 17 bytes of storage space depending on the precision and scale specified. Precision refers to the total number of digits that can be stored in the column, while scale refers to the number of digits that can be stored after the decimal point. Here is an example of how to define a column with the decimal data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Salary decimal(18,2) NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Salary. The Salary column is defined as a decimal data type with a precision of 18 and a scale of 2, which means it can store 16 digits before the decimal point and 2 digits after the decimal point.
Numeric
The numeric data type is identical to the decimal data type in every way except for the name. It is used to store fixed-point decimal values ranging from -10^38 +1 to 10^38 -1. This data type takes up 5 to 17 bytes of storage space depending on the precision and scale specified. Here is an example of how to define a column with the numeric data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Salary numeric(18,2) NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Salary. The Salary column is defined as a numeric data type with a precision of 18 and a scale of 2, which means it can store 16 digits before the decimal point and 2 digits after the decimal point.
Understanding Floating-Point Data Types
Floating-point data types are used to store decimal values with a variable number of decimal places. These values are useful when you need to store decimal numbers that have a varying number of decimal places. SQL Server provides two different floating-point data types: float and real.
Float
The float data type is used to store floating-point decimal values ranging from -1.79E + 308 to 1.79E + 308. This data type takes up 4 or 8 bytes of storage space depending on the precision specified. Precision refers to the number of bits used to represent the mantissa. Here is an example of how to define a column with the float data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Salary float(24) NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Salary. The Salary column is defined as a float data type with a precision of 24, which means it can store up to 7 digits of accurate decimal information.
Real
The real data type is used to store single-precision floating-point decimal values ranging from -3.40E + 38 to 3.40E + 38. This data type takes up 4 bytes of storage space. Here is an example of how to define a column with the real data type:
CREATE TABLE Employee (Id int IDENTITY(1,1) PRIMARY KEY,Name varchar(50) NOT NULL,Salary real NOT NULL)
In this example, we have defined a table named Employee with three columns: Id, Name, and Salary. The Salary column is defined as a real data type, which means it can store up to 7 digits of accurate decimal information.
FAQs About SQL Server Numeric Data Types
What are the benefits of using SQL Server numeric data types?
SQL Server numeric data types provide several benefits, including:
- Efficient storage of numerical data
- Ability to store different types of numerical data
- High level of precision and accuracy
How do I choose the right SQL Server numeric data type?
Choosing the right SQL Server numeric data type depends on several factors, including the range of values you need to store, the level of precision you require, and the amount of storage space you have available. Generally speaking, you should choose the smallest data type that can accommodate the values you need to store.
What happens if I try to store a value that is outside the range of a particular numeric data type?
If you try to store a value that is outside the range of a particular numeric data type, SQL Server will return an error message indicating that the value is out of range.
Can I change the data type of a column after it has been created?
Yes, you can change the data type of a column after it has been created. However, you should be aware that this can cause data loss if the new data type cannot accommodate the values that are already stored in the column.
What is the difference between the decimal and numeric data types?
The decimal and numeric data types are identical in every way except for the name. Both data types are used to store fixed-point decimal values with a high level of precision.
Which numeric data type is best for storing currency values?
The decimal data type is best suited for storing currency values because it provides the highest level of precision and accuracy.
Conclusion
In conclusion, SQL Server provides a wide range of numeric data types that can be used to store different types of numerical data. These data types are designed to handle different ranges of values and precision levels, and they are essential for any developer working with SQL Server. Understanding these data types and how to use them effectively will help you build robust and efficient databases. We hope this article has been helpful to you, Dev, in understanding SQL Server numeric data types.