odbc_foreignkeys
It seems it is common sense to say it is a god practice to free any resource when it isn´t necessary anymore.
Also, when talking about releasing the resources associated with a given result set it is a common sense to say never release a result set before it is assured to have been either commited or rolled back.
Then, the following code sequence should be the most adequate (assuming auto-commit is disabled):
odbc_commit(...);
odbc_free_result(...);
...
odbc_close(...);
odbc_free_result
(PHP 4, PHP 5)
odbc_free_result — 結果を保持するリソースを開放する
説明
bool odbc_free_result
( resource
$result_id
)結果を保持するリソースを開放します。
odbc_free_result()は、スクリプトのメモリ消費量が 多すぎることが懸念される場合にのみコールする必要があります。 全ての結果保持用メモリは、スクリプト実行が終了した際に自動的に開放されます。
パラメータ
-
result_id -
結果 ID。
返り値
常に TRUE を返します。
注意
注意:
自動コミットが無効（ odbc_autocommit() を 参照ください）な時にコミットの前に odbc_free_result() をコールすると、全ての 未解決のトランザクションは、ロールバックされます。
add a note
User Contributed Notes
odbc_free_result - [4 notes]
EMY ¶
4 years ago
rich at kastle dot com ¶
8 years ago
("Note: If auto-commit is disabled (see odbc_autocommit()) and you call odbc_free_result() before committing, all pending transactions are rolled back.")
I've looked thru the code, and that note is definitely wrong, at least in my environment (Windows/SQL Server). odbc_free_result ultimately just calls SQLFreeStmt which has NO EFFECT on outstanding transactions.
In fact, it seems it must be wrong for all environments, because the SQLFreeStmt is bound to the destruction of the result resource. So unset($result) would be just as dangerous - and you're randomly and unpredictably screwed if garbage collection reaps the result set before your transaction's done.
rogersd at island dot net ¶
11 years ago
odbc_free_result() is also the way to avoid the dreaded "Too many open cursor" error.
lm At bible in switzerland ¶
2 years ago
I use WinDev 15.0 HyperFileSQL ODBC Connector on Windows, PHP 5.2.3.
With this configuration, any result ressource obtained with odbc_exec must be freed by odbc_free_result before the next query by odbc_exec.
If the result ressource is not freed odbc_exec will return a corrupt result ressource.
example:
odbc_exec($query1);
odbc_exec($query2);
odbc_result_all();
Output: A table with empty cells