Understanding Time Data Type in SQL Server: Explained with Examples

If you are working with SQL Server, you must have come across the concept of the Time data type. The Time data type is used to store a time of day value in a variable or column of a table. In this article, we will take a closer look at the Time data type, its syntax, and usage in SQL Server. Additionally, we’ll answer some frequently asked questions to help you better understand this data type.

Syntax of Time Data Type in SQL Server

The Time data type is represented by the keyword TIME and is defined as follows:

TIME [ (fractional_seconds_precision) ]

The fractional_seconds_precision parameter specifies the number of digits in the fractional part of the second. The range of fractional_seconds_precision is 0 to 7. If the fractional_seconds_precision parameter is omitted, it defaults to 7.

Examples of Time Data Type in SQL Server

Let us take a look at some examples to understand the Time data type in SQL Server.

Example 1: Creating a Time variable

DECLARE @TimeValue TIME = ’15:30:00.00′;
SELECT @TimeValue;

In this example, we are declaring a Time variable and assigning a specific time value to it. We then select the value of this variable, which is ’15:30:00.0000000′. Here, we have not specified the fractional_seconds_precision parameter, and hence it defaults to 7.

Example 2: Creating a Time column in a table

CREATE TABLE Employee
(
EmpID INT PRIMARY KEY,
Name VARCHAR(50),
JoiningTime TIME(2)
);

INSERT INTO Employee (EmpID, Name, JoiningTime)
VALUES (1, ‘John’, ’14:30:00.00′),
(2, ‘Peter’, ’16:45:12.1234567′),
(3, ‘Mary’, ’12:12:12′);

SELECT * FROM Employee;

In this example, we are creating a table named Employee with three columns, EmpID, Name, and JoiningTime. The JoiningTime column is of Time data type with a fractional_seconds_precision parameter of 2. We then insert three rows into the table with different Time values and select all the rows from the table.

Example 3: Converting a string to Time data type

DECLARE @TimeValue TIME = ’06:30:45.12′;
SELECT CAST(@TimeValue AS VARCHAR);

In this example, we are converting a string value to Time data type using CAST() function and then converting back to VARCHAR using the same function. The output of this query will be ’06:30:45.1200000′.

FAQs about Time Data Type in SQL Server

Q1. What is the range of values that the Time data type can store?

A1. The Time data type stores time values with precision to the nanosecond. The range of values that the Time data type can store is from ’00:00:00.0000000′ to ’23:59:59.9999999′.

Q2. What is the default precision of Time data type?

A2. If the fractional_seconds_precision parameter is omitted while defining a Time variable or column, it defaults to 7.

Q3. Can we perform arithmetic operations on Time data type?

A3. Yes, we can perform arithmetic operations such as addition, subtraction, and multiplication on Time data type.

Q4. Can we compare Time values?

A4. Yes, we can compare Time values using comparison operators such as =, <>, >, >=, <, and <=. Q5. Can we use Time data type in a WHERE clause?

A5. Yes, we can use Time data type in a WHERE clause to filter rows based on specific Time values.

Q6. Can we insert NULL values in a Time column?

A6. Yes, we can insert NULL values in a Time column if the column is defined as nullable.

Conclusion

In summary, the Time data type in SQL Server is used to store time values with precision up to the nanosecond. It is widely used in databases that require the storage and manipulation of time-based data. We hope this article has helped you understand the Time data type in SQL Server better.

Code Blocks

To add code blocks in HTML, use the `

` tag. For example,








DECLARE @TimeValue TIME = '15:30:00.00';

SELECT @TimeValue;






This will display the code block as follows:


    DECLARE @TimeValue TIME = '15:30:00.00';

    SELECT @TimeValue;


Similarly, you can add other code blocks using the `


` tag.

Similar Posts