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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a743cacb4bc766c55c3aa22390e4c05e0bcf79346093a5538f86fb84ddd6a850' 
  AND token = 'UYsJBHCtloCZW9ZUaqslnlUOrHCLy7z3q+BffCMWCiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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