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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd931c03fcf2c95db86a5a1a482ff77dae9c8aa0faeb44d20dfd8f9ef4701746a' 
  AND token = 'H1dVwyqrt8BTdx0GEWGgfGHbYi6nKIuOL8gHs18/Z4E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}