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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6bf5f7828ed85920489e15d4c06e4e4e5fc8124bcd70ef4a2e64116ba6172524' 
  AND token = 'MmsnwsRON3Z2Ww2G4H8+Jz3zC2oMyc8iEWsCYEq7Iu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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