Here are a few titles, incorporating questions and focusing on the core problem: * How to Insert Date Ranges into MySQL Without Overlaps? * MySQL Date Range Insertion: Avoiding Overlaps - Solutions a

MySQL: Insert Date Range into Date Columns if Dates Don't Overlap

Problem:

Given a table with date range availability (avail), the task is to insert a new date range into the table only if it does not overlap with any existing date ranges for the given account ID (acc_id).

Proposed Solution Using a Single Insert Statement:

While it may be tempting to accomplish this in a single insert statement, sadly, it is not directly possible in MySQL alone.

Alternative Approaches:

1. SQL CHECK Constraints (Not Supported in MySQL):

   SQL CHECK constraints are the preferred method for enforcing such overlap validation. However, MySQL does not support CHECK constraints.

2. PostgreSQL CHECK Constraints:

   PostgreSQL supports CHECK constraints on tables. If switching to PostgreSQL is a viable option, this approach could be considered.

3. MySQL Triggers:

   MySQL triggers can be used to check for overlaps before insert or update operations. However, this requires an up-to-date MySQL version.

4. Application Logic:

   Typically, overlap validation is performed in application logic. A SELECT COUNT(id) ... statement can be used to check for rows that violate the new entry. If the count is greater than 0, the insert or update is aborted.

5. Additional Considerations:

   • The validation should check for any kind of overlap, including total or partial overlaps.
   • The validation should consider all existing ranges with the same acc_id.

Conclusion:

While a single insert statement may not be feasible in MySQL, alternative approaches like PostgreSQL CHECK constraints, MySQL triggers, or application logic can provide reliable overlap validation.

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