expdp compression压缩参数的测试
RDBMS 12.2.0.1
测试数据泵的compression参数。expdp帮助中该参数的说明如下：
compression默认压缩的是metadata_only,默认的压缩算法是basic。
COMPRESSION
Reduce the size of a dump file.
Valid keyword values are: ALL, DATA_ONLY, [METADATA_ONLY] and NONE.
COMPRESSION_ALGORITHM
Specify the compression algorithm that should be used.
Valid keyword values are: [BASIC], LOW, MEDIUM and HIGH.--测试，对表basicfile进行数据泵导出，该表8W行数据，其中包括lob字段。
不启用压缩，进行导出。导出的dmp文件大小1.4G，耗时1分46秒。
[oracle@redhat762100 dump]$ expdp bb/oracle dumpfile=basicfile_nocomp.dmp logfile=basicfile_nocomp0723.log directory=DUMP tables=basicfile
Export: Release 12.2.0.1.0 - Production on Tue Jul 23 08:40:59 2019
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
Starting "BB"."SYS_EXPORT_TABLE_01": bb/******** dumpfile=basicfile_nocomp.dmp logfile=basicfile_nocomp0723.log directory=DUMP tables=basicfile
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "BB"."BASICFILE" 1.408 GB 80000 rows
Master table "BB"."SYS_EXPORT_TABLE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for BB.SYS_EXPORT_TABLE_01 is:
/u01/dump/basicfile_nocomp.dmp
Job "BB"."SYS_EXPORT_TABLE_01" successfully completed at Tue Jul 23 08:42:47 2019 elapsed 0 00:01:46
[oracle@redhat762100 dump]$启用compression参数，但是compression参数设置的是meatadata_only.导出的dmp大小是1.4G(没用变化)。耗时1分44秒，少了2秒。 （几乎没用什么效果）
[oracle@redhat762100 dump]$ expdp bb/oracle dumpfile=basicfile_comp.dmp logfile=basicfile_comp0723.log directory=DUMP COMPRESSION=METADATA_ONLY tables=basicfile
Export: Release 12.2.0.1.0 - Production on Tue Jul 23 08:45:21 2019
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
Starting "BB"."SYS_EXPORT_TABLE_01": bb/******** dumpfile=basicfile_comp.dmp logfile=basicfile_comp0723.log directory=DUMP COMPRESSION=METADATA_ONLY tables=basicfile
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "BB"."BASICFILE" 1.408 GB 80000 rows
Master table "BB"."SYS_EXPORT_TABLE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for BB.SYS_EXPORT_TABLE_01 is:
/u01/dump/basicfile_comp.dmp
Job "BB"."SYS_EXPORT_TABLE_01" successfully completed at Tue Jul 23 08:47:06 2019 elapsed 0 00:01:44
启用compression参数，设置其值为all。导出的dmp文件大小为217M。耗时1分33秒。耗时少了13秒。有明显的效果。
[oracle@redhat762100 dump]$ expdp bb/oracle dumpfile=basicfile_comp.dmp logfile=basicfile_comp0723.log directory=DUMP COMPRESSION=ALL tables=basicfile
Export: Release 12.2.0.1.0 - Production on Tue Jul 23 09:13:32 2019
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
Starting "BB"."SYS_EXPORT_TABLE_01": bb/******** dumpfile=basicfile_comp.dmp logfile=basicfile_comp0723.log directory=DUMP COMPRESSION=ALL tables=basicfile
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "BB"."BASICFILE" 217.5 MB 80000 rows
Master table "BB"."SYS_EXPORT_TABLE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for BB.SYS_EXPORT_TABLE_01 is:
/u01/dump/basicfile_comp.dmp
Job "BB"."SYS_EXPORT_TABLE_01" successfully completed at Tue Jul 23 09:15:06 2019 elapsed 0 00:01:33
[oracle@redhat762100 dump]$再次针对一个不包含lob字段的小表进行导出测试。启用压缩前后导出的dmp文件大小分别为1.4M和164K。耗时分别为20秒和18秒。
[oracle@redhat762100 dump]$ expdp bb/oracle dumpfile=t1_nocomp.dmp logfile=t1_nocomp0723.log directory=DUMP tables=t1
Export: Release 12.2.0.1.0 - Production on Tue Jul 23 08:49:23 2019
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
Starting "BB"."SYS_EXPORT_TABLE_01": bb/******** dumpfile=t1_nocomp.dmp logfile=t1_nocomp0723.log directory=DUMP tables=t1
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "BB"."T1" 1.406 MB 70001 rows
Master table "BB"."SYS_EXPORT_TABLE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for BB.SYS_EXPORT_TABLE_01 is:
/u01/dump/t1_nocomp.dmp
Job "BB"."SYS_EXPORT_TABLE_01" successfully completed at Tue Jul 23 08:49:45 2019 elapsed 0 00:00:20
[oracle@redhat762100 dump]$ expdp bb/oracle dumpfile=t1_comp.dmp logfile=t1_comp0723.log directory=DUMP COMPRESSION=ALL tables=t1
Export: Release 12.2.0.1.0 - Production on Tue Jul 23 09:19:10 2019
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
Starting "BB"."SYS_EXPORT_TABLE_01": bb/******** dumpfile=t1_comp.dmp logfile=t1_comp0723.log directory=DUMP COMPRESSION=ALL tables=t1
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
Processing object type TABLE_EXPORT/TABLE/TABLE
. . exported "BB"."T1" 163.9 KB 70001 rows
Master table "BB"."SYS_EXPORT_TABLE_01" successfully loaded/unloaded
******************************************************************************
Dump file set for BB.SYS_EXPORT_TABLE_01 is:
/u01/dump/t1_comp.dmp
Job "BB"."SYS_EXPORT_TABLE_01" successfully completed at Tue Jul 23 09:19:29 2019 elapsed 0 00:00:18
[oracle@redhat762100 dump]$END