How Can I Effectively Use the DATE Datatype in SQL Server?

Utilizing the "Date" Datatype in SQL Server

Database systems frequently encounter difficulties when handling dates due to differing formats and cultural biases. SQL Server provides the "Date" datatype specifically designed to overcome these challenges.

Creating a "Date" Column

To create a "Date" column in a table, the following syntax can be used:

CREATE TABLE Orders (
  Order_ID INT PRIMARY KEY,
  Book_name VARCHAR(100),
  ISBN VARCHAR(100),
  Customer_ID INT FOREIGN KEY REFERENCES Customer,
  Order_date DATE
);

Inserting "Date" Values

When inserting dates into a "Date" column, it is crucial to utilize formats that are independent of system culture. Recommended formats include:

• Universal format: e.g., 20150730 (30th July 2015)
• ODBC format: e.g., {d'2015-07-30'}
• ISO 8601 format: e.g., '2015-07-30T00:00:00'

Querying Dates

To query dates, it is possible to use comparisons or date functions:

• To find dates before a specific date, use:

  SELECT * FROM Orders
  WHERE Order_date < '2015-08-02';

• To compare dates, use:

  SELECT * FROM Orders
  WHERE Order_date = '2015-07-30'
  OR Order_date > '2015-08-01';

Additional Considerations

• Avoid using literal dates in your code, as they may be interpreted incorrectly based on your system's culture.
• Use date functions, such as DATEADD, DATEDIFF, and GETDATE, to manipulate dates.
• Consider using the "Datetime" datatype if you need to store both date and time components.

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