DB2的世界中，表和表空间的大小主要受到pagesize和其对应寻址能力限制。
在DB2 v8中，页地址为3个字节，也就是2的24次方可用，就是16,777,216页可以被寻址，基于这个限制得到如下表空间和表大小的限制：
| # of pages | Page size | Limit of table / tablespace |
|---|---|---|
| 16,777,216 | 4 K | 64 GB |
| 16,777,216 | 8 K | 128 GB |
| 16,777,216 | 16 K | 256 GB |
| 16,777,216 | 32 K | 512 GB |
在DB2 v9中，页地址扩展为4个字节，也就是寻址能力提升4倍，具体的限制如下所示：
| # of pages | Page size | Limit of table / tablespace |
|---|---|---|
| 536,870,912 | 4 K | 2 TB |
| 536,870,912 | 8 K | 4 TB |
| 536,870,912 | 16 K | 8 TB |
| 536,870,912 | 32 K | 16 TB |
注意：在DB2 v8中，large类型的表空间只是为LOB和LONG数据类型所使用，而在DB2 v9中没有类似的限制，默认的表空间类型就是large，如果从DB2 v8升级到v9就需要手动的把表空间从regular转换为large
| ALTER TABLESPACE tablespace_name CONVERT TO LARGE |
DB2 v8中的典型报错
多所有容器扩容
db2 " ALTER TABLESPACE tablespace-name EXTEND (ALL 1000000)" DB21034E The command was processed as an SQL statement because it was not a valid Command Line Processor command. During SQL processing it returned: SQL1139N The total size of the table space is too big. SQLSTATE=54047
对其中一个容器扩容
db2 " ALTER TABLESPACE tablespace-name EXTEND (FILE '/dir/filename' 3000000)" DB21034E The command was processed as an SQL statement because it was not a valid Command Line Processor command. During SQL processing it returned: SQL1139N The total size of the table space is too big. SQLSTATE=54047
加容器
db2 " ALTER TABLESPACE tablespace-name ADD (FILE '/dir/filename' 500000)" DB21034E The command was processed as an SQL statement because it was not a valid Command Line Processor command. During SQL processing it returned: SQL1139N The total size of the table space is too big. SQLSTATE=54047
通过检查可以看到
LIST TABLESPACES SHOW DETAIL ... Tablespace ID = 8 Name = tablespace-name Type = Database managed space Contents = Any data State = 0x0000 Detailed explanation: Normal Total pages = 16388000 Useable pages = 16387840 Used pages = 16387840 Free pages = 0 High water mark (pages) = 16387840 Page size (bytes) = 4096 Extent size (pages) = 32 Prefetch size (pages) = 128 Number of containers = 4 Minimum recovery time = 2009-06-26-04.47.15.000000 ...
可以明显看到页数量已经接近了最大限制
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