This problem involves problems caused by 64-bit oracle services and 32-bit clients.

The environment is as follows: win8.1 + 64-bit oracle 11.1 as the server, the client uses 32-bit programs and does not support 64-bit oracle clients, so the 32-bit 10.2 instantclient package is used.

Problem phenomenon: Cannot connect to oracle server, plsql and sqlplus are connected normally, error while trying to retrieve text for error ORA-01019 is reported when the program is connected.

The description of this error in the Oracle documentation is:

ORA-01019: unable to allocate memory in the user
Cause: The user side memory allocator returned error.

Action: Increase the processes heap size or switch to the old set of calls.

 

Solution:

The reason for this problem seems to be that ODBC does not use the driver provided by Oracle, but uses the driver provided by the system other than ORACLE_HOME. Obviously it is not a memory issue. So solve the first step:

1. Add ORACLE_HOME to the environment variable to point to the 64-bit installation directory instead of the instantclient directory. I think this step can let windows use the matching file to drive

   After doing the first step, and then connecting again, the error message becomes an error that memory cannot be allocated. Then the second step

2. Replace 10.2 Instantclinet package with 11.1 matching 32-bit instantclient package

    After changing, the connection is normal.

 

Both tns_admin and path in the environment variables can point to the location path of the 32-bit instantclient package.