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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6c4e8e1f6493989bd0c971e0d0681c2fa8680fb6eef6146f854b910d8cb7450' 
  AND token = 'rT/IyiUK+9ps3x3NXQ6K2dCiAOsF3EBdtdG5EE4GgWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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