SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '691bc997c041121e01ceaac6f8f510dc64bd59d879f140b475176ebfb291f186' 
  AND token = '0s+otMmkVm0xQP0x3WFmZbr2MRAFO9yndTPNPQzMDQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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