In MySQL, it's common to use a simplified syntax like `SELECT constant FROM dual`
which is equivalent to just `SELECT constant`.
This syntax is often used by BI tools when utilizing MySQL connectors to verify connection validity.
To enhance compatibility and ensure seamless integration with such tools,
we have now implemented this feature in Doris.
### Key Changes:
- Doris now interprets `SELECT constant FROM dual` as `SELECT constant`, aligning with MySQL's behavior.
- This update ensures that BI tools can use standard MySQL connectors without modifications or errors when connecting to Doris.
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