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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9310965599ba6fb2e5e136892b2bd9fe879f8e8b3c001bc2f07702f4a71e46a' 
  AND token = 'o53fDMtql2cpC3fY8gKyTyjVMhj6sr7CiQT5UEbClLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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