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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '855fb4e9b811afb16c69def0c03734b21904558b60416d8aa579f4c979083f99' 
  AND token = '3tmvU6tdMu4ZPcw7Uv5W3le4f7yU/dZh/Y1xnOnHpcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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