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Don Burleson Blog 







ORA-20000: ORU-10027: buffer overflow, limit of 2000 bytes

Oracle Database Tips by Donald BurlesonJuly 21, 2015

Question:  I am using a procedure to try to pull data for reporting purposes.  I am getting the following ORA-20000 with ORU-10027 error:

ORA-20000: ORU-10027: buffer overflow, limit of 2000 bytes

I need the output for a report, so I cannot just disable it to eliminate the ORA-20000 ORU-10027.

What can I do to get rid of the ORA-20000 ORU-10027 error?

Answer:  DBMS_OUTPUT has different default buffer sizes, depending on your Oracle version.  For your system, the limit is 2000 bytes.

You can increase the buffer up to 1,000,000 using the following PL/SQL statement:


The SQL*Plus statement to achieve the same result is:

set serveroutput on size 1000000

Starting with Oracle release 10g, it is possible to use the following unlimited buffer settings:

  • PL/SQL: DBMS_OUTPUT.ENABLE (buffer_size => NULL);
  • SQL*Plus: set serveroutput on size unlimited

Since I do not have the code you are running, I cannot do a full diagnostic on it.  If the DBMS_OUTPUT settings in the code are acceptable for your version of Oracle and the client (SQL*Plus, etc.) you are using and you are still getting the ORA-20000 ORU-10027 buffer overflow error for the stated limits, you should check your full code to determine whether there are any other calls that include conflicting DBMS_OUTPUT.ENABLE settings that might be overriding yours.

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