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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3f1801efa1c95974c2904828d0bbc9e7076a59c1e45e661a0f6fe14d2dc5ead' 
  AND token = 'QflcdiEeijUe0daRMsvwHqpzHiyypBg75t5qki+65RQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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