SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '147afa135ec5cecc0a97934bafb4f956f79b7607031370272078d78c41c88978' 
  AND token = 'DMk1s0ZpMifl2wwtdmbANs/Cx2LMLx1maO0YUaWNSRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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