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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '18e8a2dac4da82b6585c922b0db1f2d15f02bc22ea4be5fd27aabe9dc20b8561' 
  AND token = 'F29ecWP0Lht8V5lXo+q6Rtgfs2luLK77x9MVgOT0jEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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