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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5262e31b7e5946b40dc3d0bc39e36b407059d02cac0fc1fac2ba6ce9b4d58b4e' 
  AND token = '8Eh8L1ImcyK3vp6qeLO7v0lat6PrENEsXqXwgCdqjR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00078

JSON explain

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