SQL*Plus looks for libraries relative to the ORACLE_HOME directory. If this variable is not set, the executable cannot find its dependencies.

Action: Verify the variable is set by echoing it:

echo $ORACLE_HOME

If it returns a blank line or an incorrect path, set it to your Oracle installation directory (e.g., /u01/app/oracle/product/19.0.0/dbhome_1):

export ORACLE_HOME=/path/to/your/oracle/home

  • Environment Configuration Issues

  • Installation Problems

  • File System Permissions

    • This is the most frequent fix. On Linux, the dynamic linker needs to know where to find shared libraries (like libsqlplus.so). If LD_LIBRARY_PATH does not include the Oracle lib directory, Error 57 occurs.

    Action: Add the Oracle library path to the variable:

    export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH

    Note: If you are using a shell like csh or tcsh, use setenv instead of export.

    This is the most common environment for this error. It is almost always caused by incorrect environment variables.