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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6415f19f4ccaa3b0417b3a6082d9f79e5ee1c6546fc69b37e04e8c77bea08da' 
  AND token = 'n7+Z0GCIJ9x0DvMrhU2TeCzgUEQS3GeZE2aEzSzezvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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