In SQL, dates are used to represent points in time or intervals. SQL provides various data types and functions to work with dates and perform operations like storing, retrieving, comparing, and manipulating date values. Here are some important aspects of working with dates in SQL:

1. Date Data Types: SQL supports several date-related data types, including:

- DATE: Represents a date without a time component (e.g., '2023-07-14').
- TIME: Represents a time without a date (e.g., '12:34:56').
- DATETIME or TIMESTAMP: Represents a combination of date and time (e.g., '2023-07-14 12:34:56').
- INTERVAL: Represents a duration or time interval (e.g., '1 day', '2 hours', '30 minutes').

The specific date data types available may vary depending on the database system you are using.

2. Date Functions: SQL provides various built-in functions to work with dates. Some commonly used functions include:

- CURRENT_DATE: Returns the current date.
- CURRENT_TIME: Returns the current time.
- CURRENT_TIMESTAMP or NOW(): Returns the current date and time.
- DATEPART or EXTRACT: Extracts specific parts (year, month, day, hour, minute, etc.) from a date.
- DATEADD or DATE_SUB: Performs date arithmetic by adding or subtracting intervals from a date.
- DATEDIFF or DATE_PART: Calculates the difference between two dates in a specific interval (days, months, years, etc.).
- DATE_FORMAT or TO_CHAR: Formats a date value into a specific string representation.

The syntax and available functions may vary across different database systems, so refer to the documentation of your specific database for accurate details.

3. Date Comparisons: SQL allows you to compare dates using comparison operators (>, <, =, etc.) to perform operations like filtering data based on specific date conditions.

4. Date Manipulation: SQL provides capabilities to manipulate dates, such as adding or subtracting intervals, truncating time components, or converting between different date formats. These operations can be useful for performing calculations or formatting date values according to specific requirements.

5. Date Constraints: SQL allows you to define constraints on date columns to enforce data integrity. For example, you can specify a minimum or maximum date value that can be stored in a column using constraints like CHECK or FOREIGN KEY.

6. Date Formats: SQL databases typically have their own default date formats. However, you can often customize the date format for displaying or inserting dates using appropriate functions or formatting options specific to your database system.

Remember that date-related features and syntax can vary across different database systems. It's essential to consult the documentation of your specific database system for accurate details on working with dates in SQL.