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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4992b5ed5b2ff96a8c2e8ae4c0ef25f40ab8be896c3cae4c7ba405c031a6dd2' 
  AND token = 'uUEtqNycltXiU+lznl0AyN7kVVEAG+v1OPKU3U32P5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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