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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a6df4475fcd84d32ac2d4fe7bdd081e0fc1a8e608fde17e8debe0b60fdf5312d' 
  AND token = 'S4jnmOTrDVUq7yGCE0VxKYXDd9TIkq+poiG5H0z4ruo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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