This topic contains some questions and answers specific to Database Connectors for ODBC.
Question
Can I open tables in different databases and share the data?
Answer
Yes. But you must set up the data sources one at a time. For example, you could first set your data source to be Oracle and open Oracle tables, and then you could change the data source to Access and open Access tables.
Remember, you can set up data sources dynamically at run time by adding a line like this before the statement that opens the file:
SET ENVIRONMENT "A_ODBC_DATASOURCE" TO "data source name"
Question
I keep receiving an error message saying that my login is invalid. But I’m sure I’m using the correct username and password.
Answer
All usernames, passwords, and database names are case-sensitive. Be sure that you are typing the names exactly as they are set up.
Question
I’m using Microsoft Access version 2.0, and I’m having trouble accessing/writing tables from my COBOL program.
Answer
Check the version of the Access driver you are using. Microsoft Access version 2.0 requires version 2.0 of the driver. If you are using a previous version of the driver, the run-time system will generate errors. To determine the version number of your driver, you can run the Database Connectors for ODBC driver test program DRVTST32.EXE (32-bit version).
Question
I’m noticing some performance degradation when accessing my ODBC data source. What is the cause of this?
Answer
You may notice some performance impact if you were previously accessing Vision indexed files directly. This is because ODBC adds a software layer between your applications and your data sources. In return for minor performance impact, you can reap the benefits of database independence and enhanced portability. Overall performance depends on several factors, including your network configuration and your specific data source.
Question
I wrote data with my Database Connectors for Oracle (or Informix) product. When I try to read it with Database Connectors for ODBC, the data is not the same.
Answer
By necessity, the BINARY data type is implemented differently in Database Connectors for ODBC than it is in Database Connectors for Oracle or Informix. For this reason, writing data with one Database Connectors product and then reading it with another will probably produce different results. Future releases of Database Connectors for Oracle and Informix will address this problem.
Question
When I create a table, I get an error saying I have placed too many BLOBs (binary large objects) in my table.
Answer
Some databases have restrictions about the number of BLOBS that can be placed into a single table. To work around this restriction, you can specify the configuration variable A_ODBC_USE_CHAR_FOR_BINARY. This allows you to encode binary data in hexadecimal and write it out as CHAR data instead of BINARY. See A_ODBC_USE_CHAR_FOR_BINARY for more information on this variable.
Question
Are there any library routines that do not work with or would not make sense to use with Database Connectors for ODBC?
Answer
Yes. The C$COPY and C$RENAME library routines do not work with Database Connectors for ODBC.