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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'df66ff3c2bb386257db8936bc1d3829a2dcf04f6ff57ee8df71c0211a2d23bd1' 
  AND token = 'wrhXBDWFVHr5tvdvaGe/AwRXhR6pNVckOO2mAWH5PWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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