Shulou(Shulou.com)06/01 Report--

1. Suppose it takes you 8 hours to import to 99%, but in the end, you don't have enough data in the table space and the import reports an error. What should I do?

Will this import report an error? Will it roll back?

Not enough space is a fatal mistake. It rolls back. But there's a parameter, resurable, resurable =y resurable_timeout=28800, that allows us to hang and wait for a while.

2. Importing large amounts of data takes a long time. We need to know, where are we? Suspended? Are you still importing?

First, set the response parameter feedback= 1000000. Second, look at the insertion log.

Third, look at the relevant process cpu in the resource manager, whether the hard disk is in use, and fourth, see whether the written file has changed.

Fifth, the best way is to see that there is a sql_id in the session v$session, which records what sql statements the current session is executing.

3. How to import faster?

Set table nologing.direct path import. Do not import index for now.

insert /*+append*/ into card_trade_detail

4. Operation of cutting large files. Large files such as 300 gigabytes, you will encounter such problems, for example, you copy a 300 gigabyte file from the hard disk to the mobile hard disk, just start very fast, 600M/s, to 30M/s later, headache bar. So we need to cut the file when we export. Cutting large files into smaller pieces, such as 5G copies, is also slow.

5. Here are some empirical data

(1) 4.86 million 225 seconds, each segment 840M 4.51 million: 49 seconds 4.97 million: 53 data files for one year 434G

The current data volume is 110 million, and the index created is:

create index idx_ctd_card_inner_no_gl on CARD_TRADE_DETAIL(card_inner_no) global tablespace cardidx01;

Elapsed time: 369 seconds, index size is 4G .

(2) 110 million data index uk_ctd_gl_1 7 fields to establish a unique index, took 253 seconds, index size of 6.8G

(3)18 The data index uk_ctd_gl_1 is composed of 7 fields to establish a primary key index, and the index size is 144G;

(4)Import 300 gigabytes of data and insert it on a dellr730 machine for 8 hours.

On the dellr730 machine, the 1.8 billion data index uk_ctd_gl_1 7 fields establish the primary key index, the index size is 112G, and the establishment takes 52 minutes.

(5)And finally, one of the more ridiculous deployments: exporting 1.8 billion 500 gigabytes of data took 40 minutes. Export 225 gigabytes of data to USB flash drive in 5 hours. Transfer from USB flash drive to client computer for 1 hour. Copy from midship to aix system, 6 hours. The import time is 5 hours.

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