SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16cdaedd77a541f88814e0abae6a6dc895ca2b0add50099ca0ecb5aed41e7670' 
  AND token = 'ijr0mVGubhX2Qfyc6ueah4v0mYomccSasWjO8DS6hzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}