Logical Database Limits

Item Type Limit
CREATE MATERIALIZED VIEW definition Maximum size 64K Bytes
GROUP BY clause Maximum length The GROUP BY expression and all of the nondistinct aggregate functions (for example, SUM, AVG) must fit within a single database block.
Indexes Maximum per table Unlimited
total size of indexed column 75% of the database block size minus some overhead
Columns Per table 1000 columns maximum
Per index (or clustered index) 32 columns maximum
Per bitmapped index 30 columns maximum
Constraints Maximum per column Unlimited
Subqueries Maximum levels of subqueries in a SQL statement Unlimited in the FROM clause of the top-level query

255 subqueries in the WHERE clause

Partitions Maximum length of linear partitioning key 4 KB - overhead
Maximum number of columns in partition key 16 columns
Maximum number of partitions allowed per table or index 1024K - 1
Rows Maximum number per table Unlimited
Stored Packages Maximum size PL/SQL and Developer/2000 may have limits on the size of stored procedures they can call. The limits typically range from 2000 to 3000 lines of code.

See Also: Your PL/SQL or Developer/2000 documentation for details

Trigger Cascade Limit Maximum value Operating system-dependent, typically 32
Users and Roles Maximum 2,147,483,638
Tables Maximum per clustered table 32 tables
Maximum per database Unlimited


The limit on how long a SQL statement can be depends on many factors, including database configuration, disk space, and memory


When an object instance exists in memory, there is no fixed limit on the number of attributes in the object. But the maximum total amount of memory consumed by an object instance is 4 GB.When an object instance is inserted into a table, the attributes are exploded into separate columns in the table, and the Oracle 1000-column limit applies.