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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '833d8208d5ffc61efe4613aba86e52cf9ef1dd8da7ce95f449e3f6dc71be602c' 
  AND token = '6Ct3Xn3ZkEcycTrMOt7awvgeqrKSoS+VFnV47XKismA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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