Oracle AI Database 26ai — Wide Tables

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 Before Oracle AI Database 26ai, the maximum number of columns allowed in a table or view was limited to 1000. If this limit was exceeded, Oracle would raise the following error:

ORA-01792: maximum number of columns in a table or view is 1000

Starting with Oracle AI Database 26ai, this limitation has been significantly expanded, allowing each table to contain up to 4096 columns.

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To take advantage of this new capability, the initialization parameter max_columns must be set to extended:

SQL> alter system set max_columns=extended scope=spfile;
System altered

SQL>startup force

After restarting the database, you can create or modify tables with more than 1000 columns. The following example demonstrates how to add columns up to this new limit:

SQL> declare
  2  comm varchar2(100);
  3  begin
  4    for i in 2..4095 loop
  5     comm:='alter table  tb add c'||''||i||' number';
  6     execute immediate comm;
  7    end loop;
  8  end;
  9  /
  PL/SQL procedure successfully completed

Finally, verify the number of columns in the table:

SQL> select count(*) from dba_tab_columns p where p.table_name='TB';
  COUNT(*)
----------
      4095

This result confirms that Oracle AI Database 26ai successfully supports wide tables with significantly more columns than previous versions.

Vahid Yousefzadeh

Written by Vahid Yousefzadeh

I have been a DBA since 2011 and I work with Oracle technology. Linkdin: linkedin.com/in/vahidusefzadeh telegram channel ID:@oracledb vahidusefzadeh@gmail.com

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