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Storing Date and Time Data with Precision Using SQL Server DATETIME2

SQL Server DATETIME2 is a data type used to store date and time values in Microsoft SQL Server. This data type is a significant improvement over the old DATE and DATETIME data types because it provides more flexibility and range.

In this article, we will provide an overview of DATETIME2 data type, syntax and components, default string literal format, and examples of using DATETIME2 in SQL Server. Overview of SQL Server DATETIME2:

The DATETIME2 data type is used to store date and time values in SQL Server.

It has a higher precision for fractional seconds and an extended range for both dates and times. The syntax for DATETIME2 follows this pattern:

DATETIME2 [ (fractional seconds precision) ]

The fractional seconds precision specifies the number of digits that can be stored for fractional seconds.

The value can range from 0 to 7 for DATETIME2. The components of a DATETIME2 value consist of a date and a time.

The date component can be any valid date in the range of January 1, 0001, to December 31, 9999. The time component can be any valid time in the range of 00:00:00.0000000 to 23:59:59.9999999.

By default, SQL Server DATETIME2 data type has a storage size of 6 bytes for precision up to 2 fractional seconds, and 7 to 8 bytes for higher precision. This size can affect table space and DBMS performance.

Default string literal format of DATETIME2:

SQL Server DATETIME2 data type has a default string literal format in the format of “YYYY-MM-DD hh:mm:ss[.fractional seconds]”. This format follows the ISO 8601 standard, which is an international standard for representing date and time.

Using this format, DATETIME2 value always starts with the year as YYYY. MM represents the month of the date, DD represents the day of the date, hh represents the hour of the day, mm represents the minutes of the hour, ss represents the seconds of the minute, and fractional seconds represent the number of decimal places stored.

SQL Server DATETIME2 Example:

Now that we have outlined the basics of SQL Server DATETIME2, let’s look at some practical examples of using this data type. 1.

Inserting current date and time into DATETIME2 column:

To insert the current date and time into a DATETIME2 column, we need to use the INSERT statement along with the GETDATE() function. The GETDATE() function returns the current system date and time as a DATETIME2 value.

Here’s an example of how to insert the current date and time into a DATETIME2 column:

INSERT INTO my_table (created_at)

VALUES (GETDATE());

In this example, we are inserting the current date and time into a column called created_at in a table called my_table. 2.

Inserting literal value into DATETIME2 column:

We can also insert a literal value into a DATETIME2 column. For instance, if we want to insert the date ‘2022-01-01′ and time ’09:30:00’ into a DATETIME2 column, we can use the VALUES keyword in the INSERT statement.

Here’s an example of how to insert a literal value into a DATETIME2 column:

INSERT INTO my_table (created_at)

VALUES (‘2022-01-01 09:30:00’);

In this example, we are inserting the literal value of ‘2022-01-01 09:30:00’ into a column called created_at in a table called my_table. 3.

Setting default value for DATETIME2 column:

We can also set a default value for a DATETIME2 column when creating a table or altering its schema. This value will be used automatically if no value is specified during the INSERT statement.

Here’s an example of how to set a default value for a DATETIME2 column:

ALTER TABLE my_table

ADD CONSTRAINT df_created_at

DEFAULT CURRENT_TIMESTAMP

FOR created_at;

In this example, we are adding a default constraint called df_created_at to a column called created_at in a table called my_table. The constraint sets the default value of the current system date and time (using the CURRENT_TIMESTAMP function) for the created_at column.

Conclusion:

In conclusion, SQL Server DATETIME2 data type is a flexible and precise way to store date and time values in Microsoft SQL Server. It provides fractional seconds precision and can store a range of dates and times.

Understanding its syntax and components, default string literal format, and practical examples of using it in SQL Server will help you work with this type more efficiently.

Using DATETIME2 to store both date and time data in a table

SQL Server DATETIME2 is a data type that stores date and time data with high precision and accuracy. Using DATETIME2, we can store both date and time data in a table.

In this article, we will discuss the advantages of using DATETIME2 for storing date and time data, creating a table with DATETIME2 column, and using DATETIME2 in queries and operations. Advantages of using DATETIME2:

When it comes to storing date and time data, the accuracy and precision of the data are vital.

Using DATETIME2 can provide benefits over other data types such as DATE and DATETIME. Some of the advantages of using DATETIME2 are:

1.

Higher precision: DATETIME2 data type provides greater precision than the other date and time data types in SQL Server. We can specify fractional seconds precision up to 7 digits with DATETIME2.

2. Extended range: The range of valid dates and times that can be stored in DATETIME2 is from January 1, 0001, to December 31, 9999, with precision up to 100 nanoseconds.

Hence, we can store dates and times with high accuracy and precision. 3.

Storage space: DATETIME2 data type requires more storage space than other date and time data types. However, it provides high precision and accuracy in storing date and time data.

Creating table with DATETIME2 column:

To create a table with a DATETIME2 column, we can use the CREATE TABLE statement. Syntax:

CREATE TABLE table_name

(

column1 datatype,

column2 datatype,

….. columnN datatype,

);

Here’s an example of creating a table with a DATETIME2 column:

CREATE TABLE example_table

(

Id INT PRIMARY KEY,

Created_At DATETIME2(3) DEFAULT GETDATE(),

Updated_At DATETIME2(3)

);

In this example, we are creating a table called example_table with three columns: Id, Created_At, and Updated_At. The Id column is an integer column and the primary key of the table. The Created_At column is a DATETIME2 type column with precision up to 3 fractional seconds.

We are setting the default value of the column to the current system date and time using the GETDATE() function. The Updated_At column is also a DATETIME2 type column with precision up to 3 fractional seconds, which we will populate manually later.

Using DATETIME2 in queries and operations:

Once we have created a table with a DATETIME2 column, we can manipulate and query the data using various SQL operations. 1.

Selecting data:

To select all data from a table with a DATETIME2 column, we can use the SELECT statement. Syntax:

SELECT column1, column2, …..

FROM table_name;

Here’s an example of selecting data from the example_table:

SELECT *

FROM example_table;

It will return all columns and their respective data from the example_table. 2.

Filtering data:

To filter data from a table, we can use the WHERE clause in the SELECT statement. Syntax:

SELECT column1, column2, …..

FROM table_name

WHERE condition;

Here’s an example of selecting data from example_table, where the Created_At column has a specific date:

SELECT *

FROM example_table

WHERE Created_At = ‘2022-06-15 09:30:00’;

In this example, we are filtering data where the Created_At column is ‘2022-06-15 09:30:00’. We can use comparison operators such as less than (<), greater than (>), less than or equal to (<=), and greater than or equal to (>=) to filter using dates.

3. Arithmetic operations:

We can perform arithmetic operations on DATETIME2 columns.

For instance, we can add or subtract hours, minutes, seconds, and days from a DATETIME2 column to get a new date and time value. Syntax:

SELECT DATEADD(datepart, number, date),

DATEDIFF(datepart, startdate, enddate)

FROM table_name;

Here’s an example of adding 10 days and 5 minutes to the Created_At column in example_table:

SELECT Id, Created_At, DATEADD(MINUTE, 5, DATEADD(DAY, 10, Created_At)) AS New_Date

FROM example_table;

In this example, we are adding 10 days and 5 minutes to the Created_At column and giving it an alias name as New_Date. We are using the DATEADD function to add 10 days and 5 minutes to the Created_At column.

Conclusion:

In conclusion, using DATETIME2 to store both date and time data in a table can provide greater precision and range than other data types. Creating a table with a DATETIME2 column requires specifying precision and default values.

We can use SQL operations to manipulate and query the data, including filtering data with WHERE clause and using arithmetic operations such as adding and subtracting dates to get new values. Overall, DATETIME2 data type is an ideal way to store date and time data in Microsoft SQL Server with high accuracy and precision.

In conclusion, SQL Server DATETIME2 data type provides greater precision and range than other data types for storing date and time data in Microsoft SQL Server. Using DATETIME2 in a table requires creating columns with specific precision and default values.

We can use SQL operations like filtering and arithmetic operations to manipulate and query the data stored in DATETIME2 columns. By using DATETIME2, we can store date and time data with high accuracy and precision, which is crucial for many applications.

Overall, understanding and utilizing DATETIME2 is important for developers and database administrators to ensure the integrity and accuracy of their data.

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