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Comparing Datetime Values with Only Date in SQL Server
When querying a database for records created on a specific date, it's important to consider the datetime nature of the column. Comparing a datetime field with only the date part using the equals operator (e.g., U.DateCreated = '2014-02-07') may not return the expected results.
Solution 1: Using Date Ranges
To accurately compare a datetime field with only the date part, use a date range:
Select * from [User] U where U.DateCreated >= '2014-02-07' and U.DateCreated <p>This approach ensures that records created on '2014-02-07' are retrieved, regardless of the time component.</p><p><strong>Reason for Avoiding Functions in WHERE Clause</strong></p><p>It's not recommended to use functions (e.g., convert) in the WHERE clause for two main reasons:</p><ol> <li> <strong>Loss of Index Optimization:</strong> Functions on data may prevent the optimizer from using indexes, resulting in slower queries.</li> <li> <strong>High Computational Overhead:</strong> Functions can introduce significant computational overhead when applied to large datasets.</li> </ol><p><strong>Best Practice for Date Ranges</strong></p><p>For optimal performance and accuracy when querying date and time ranges, it is best practice to use the following format:</p><pre class="brush:php;toolbar:false">WHERE col >= '20120101' AND col
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