Oceanbase 支持的block size范围是多少 ？

通过查询Oceanbase Oracle租户模式下的建脚本，可以看到一些有意思的属性，这么我们来分别测试一下。

obclient> CREATE TABLE t1_2k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 2048 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_4k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 4096 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.03 sec)
obclient> CREATE TABLE t1_8k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 8192 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.03 sec)
obclient> 
obclient> CREATE TABLE t1_32k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 32768 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_64k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 65536 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_128k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 131072 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_256k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 262144 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_512k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 524288 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.05 sec)
obclient> CREATE TABLE t1_1024k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 1048576 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> CREATE TABLE t1_2048k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 2097152 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
ERROR-00600: internal error code, arguments: -5258, Invalid block size, block size should between 16384 and 1048576
obclient> 

从上述测试来看，目前Oceanbase 2.2版本最大对于blocksize的支持范围是2k-1024k；远超Oracle 的支持范围，由此也可以初步判断oceanbase的单表支持应该是非常巨大的。

另外从上面测试来看，大家可以看到,虽然提示支持的范围是16k-1024k，但实际上我测试2k-8k都可以的。这或许是一个小bug ？

突然还有个小疑问，能否支持非标准block size呢？ 测一下：

obclient> CREATE TABLE t1_3k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 3072 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient> insert into t1_3k select owner,object_name from dba_objects;
Query OK, 269 rows affected (0.25 sec)
Records: 269  Duplicates: 0  Warnings: 0
obclient> commit;
Query OK, 0 rows affected (0.00 sec)
obclient> select * from t1_3k where rownum < 5;
+-------+-------------------------------------------------------+
| OWNER | OBJECT_NAME                                           |
+-------+-------------------------------------------------------+
| ROGER | KILLDB                                                |
| ROGER | __idx_1100611139453779_IDX_OWNER                      |
| ROGER | TEST_RECOVER                                          |
| ROGER | __idx_1100611139453782_RECYCLE_OBIDX_1590579268121989 |
+-------+-------------------------------------------------------+
4 rows in set (0.00 sec)

很有意思。。。还支持3k block size. 其实还有更好玩的。。。。

obclient> CREATE TABLE t1_5k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 5100 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)
obclient>

应该说支持任意block size的.前面测试最大支持1024k，那么最小是多少呢 ？

obclient> CREATE TABLE t1_1k (
->   "OWNER" VARCHAR2(128) DEFAULT NULL NOT NULL,
->   "OBJECT_NAME" VARCHAR2(128),
-> ) COMPRESS FOR ARCHIVE REPLICA_NUM = 1 BLOCK_SIZE = 1 USE_BLOOM_FILTER = FALSE TABLET_SIZE = 134217728 PCTFREE = 10;
Query OK, 0 rows affected (0.04 sec)

Omg。。。 最小支持1个byte的block size。 当然这就玩玩，生产环境肯定不能这样设置。。。那没发跑业务。