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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4a1f0e3ea6ffee0e8bf054ca70abc83abccaf657832bf425f6b19c3b4ab1bd9' 
  AND token = 'nribnoQ/gRQ4iwumm8n93Z9gPM5+BVMUf6JdnboPDos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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