Reusing prepared statement hangs about ocilib

[vrogier]

Hi,

This is a misuse of the API.
Host bind variables must remain valid during the lifetime of the prepared statement.
In your code you are deleting these variables while still being bounded to the statement.
As you did not set the option to allow rebinding variables, second binding calls fail and the statement still uses previously bounded and destroyed host variables leading accessing dandling pointers and thus undefined behaviour.
The concept of bind variables is to bind them once and reuse them across executions. You just need to update their content.

Regards,

Vincent

[AIIleG]

Oh I see, the binding is still part of the prepare stage so to say. Well, that works with one exception: I have to use OCI_LobTruncate() for every consecutive run because OCI_LobWrite() appends the text otherwise.
In practice however, at least for things like number and varchar, using OCI_AllowRebinding() is much better because declaring all variables in advance (the insert values are often generated within loops) is usually not possible or would require to copy the content to the already bound variables every time. The latter is the case for lob or date anyway so for them it doesn't matter.

Thanks for the reply and sorry for the false bugreport.