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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fdf75ef8b01b3c620716d6df49512e192ce42e1048c7bbdb299cd05913c32b83' 
  AND token = 'jNIKbhSZ+iY5b9rsTOjkESe7oyUP/Vl7x8OaPH6BPOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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