Deepgreen & Greenplum DBA小白普及课之一（一般问题解答）

tpch=# \d region
                             Append-Only Columnar Table "public.region"
   Column    |          Type          |                          Modifiers                           
-------------+------------------------+--------------------------------------------------------------
 r_regionkey | integer                | not null default nextval(‘region_r_regionkey_seq‘::regclass)
 r_name      | character(25)          |
 r_comment   | character varying(152) |
Checksum: t
Distributed by: (r_regionkey)

tpch=# \dn
       List of schemas
        Name        |  Owner 
--------------------+---------
 gp_toolkit         | dgadmin
 information_schema | dgadmin
 pg_aoseg           | dgadmin
 pg_bitmapindex     | dgadmin
 pg_catalog         | dgadmin
 pg_toast           | dgadmin
 public             | dgadmin
(7 rows)

tpch=# select objname,actionname,statime from pg_stat_operations  where objname like ‘region‘;
 objname | actionname |            statime           
---------+------------+-------------------------------
 region  | CREATE     | 2017-05-21 00:32:28.672208+08
 region  | ANALYZE    | 2017-06-30 06:55:57.658525+08
(2 rows)

查看表的大小：
tpch=# select pg_size_pretty(pg_relation_size(‘public.customer‘));
 pg_size_pretty
----------------
 122 MB
(1 row)
查看表和索引的大小：
tpch=# select pg_size_pretty(pg_total_relation_size(‘public.customer‘));
 pg_size_pretty
----------------
 155 MB
(1 row)

tpch=# select schemaname ,round(sum(pg_total_relation_size(schemaname||‘.‘||tablename))/1024/1024) "Size_MB" from pg_tables where schemaname=‘public‘ group by 1;
 schemaname | Size_MB
------------+---------
 public     |   10698
(1 row)

tpch=# select pg_size_pretty(pg_database_size(‘tpch‘));
 pg_size_pretty
----------------
 10 GB
(1 row)

tpch=# select datname,pg_size_pretty(pg_database_size(datname)) from pg_database;
  datname  | pg_size_pretty
-----------+----------------
 tpch      | 10 GB
 postgres  | 111 MB
 tpch_1g   | 1100 MB
 template1 | 29 MB
 template0 | 27 MB
(5 rows)

select schemaname,tablename,round(sum(pg_total_relation_size(schemaname "" ‘.‘ "" partitiontablename))/1024/1024) "MB"
from pg_partitions where tablename=‘employee_daily‘ group by 1,2;
schemaname " tablename      " MB
-----------+----------------+-----
public     " employee_daily " 254

tpch=# \h alter table
Command:     ALTER TABLE
Description: change the definition of a table
Syntax:
ALTER TABLE [ONLY] name RENAME [COLUMN] column TO new_column

ALTER TABLE name RENAME TO new_name

ALTER TABLE name SET SCHEMA new_schema

ALTER TABLE [ONLY] name SET
     DISTRIBUTED BY (column, [ ... ] )
   | DISTRIBUTED RANDOMLY
   | WITH (REORGANIZE=true|false)

ALTER TABLE [ONLY] name action [, ... ]

ALTER TABLE name
   [ ALTER PARTITION { partition_name | FOR (RANK(number))
                     | FOR (value) } partition_action [...] ]
   partition_action

where action is one of:
  ADD [COLUMN] column_name type
      [ ENCODING ( storage_directive [,...] ) ]
      [column_constraint [ ... ]]
  DROP [COLUMN] column [RESTRICT | CASCADE]
  ALTER [COLUMN] column TYPE type [USING expression]
  ALTER [COLUMN] column SET DEFAULT expression
  ALTER [COLUMN] column DROP DEFAULT
  ALTER [COLUMN] column { SET | DROP } NOT NULL
  ALTER [COLUMN] column SET STATISTICS integer
  ADD table_constraint
  DROP CONSTRAINT constraint_name [RESTRICT | CASCADE]
  DISABLE TRIGGER [trigger_name | ALL | USER]


tpch=# \h create index
Command:     CREATE INDEX
Description: define a new index
Syntax:
CREATE [UNIQUE] INDEX name ON table
       [USING btree|bitmap|gist]
       ( {column | (expression)} [opclass] [, ...] )
       [ WITH ( FILLFACTOR = value ) ]
       [TABLESPACE tablespace]
       [WHERE predicate]

dgadmin@flash:~$ PGOPTIONS=‘-c gp_session_role=utility‘ psql -p 25432 -h flash -d postgres
psql (8.2.15)
Type "help" for help.
postgres=# \q

Master节点的数据库日志存在$MASTER_DATA_DIRECTORY/pg_log/目录下，文件名根据数据库的log_filename参数生成。
dgadmin@flash:~$ gpconfig -s log_filename
Values on all segments are consistent
GUC          : log_filename
Master  value: gpdb-%Y-%m-%d_%H%M%S.csv
Segment value: gpdb-%Y-%m-%d_%H%M%S.csv
     默认安装的日志文件格式为：$MASTER_DATA_DIRECTORY/pg_log/gpdb-yyyy-mm-dd_000000.csv
     gpstart\gpstop\gpstate和另外utility生成的日志存储在：~gpadmin/gpAdminLogs/目录下

     Primary Segment日志位置用下面语句查询：select dbid,hostname,datadir||‘/pg_log‘ from gp_configuration where content not in (-1) and isprimary is true;
     Mirror Segment日志位置用下面语句查询：Primary Segment日志位置用下面语句查询：select dbid,hostname,datadir||‘/pg_log‘ from gp_configuration where content not in (-1) and isprimary is false;

tpch=# \df pub*.*test*
                       List of functions
 Schema "   Name      " Result data type " Argument data types
--------+-------------+------------------+---------------------
 public " bugtest     " integer          "
 public " test        " boolean          " integer
 public " test        " void             "
(3 rows)

dgadmin@flash:/dgdata/primary/dg0/pg_log$ gpstate -Q
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-Starting gpstate with args: -Q
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-local Greenplum Version: ‘postgres (Greenplum Database) 4.3.99.00 build Deepgreen DB‘
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-master Greenplum Version: ‘PostgreSQL 8.2.15 (Greenplum Database 4.3.99.00 build Deepgreen DB) on x86_64-unknown-linux-gnu, compiled by GCC gcc (Ubuntu 4.9.4-2ubuntu1~14.04.1) 4.9.4 compiled on May 18 2017 05:19:19‘
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-Obtaining Segment details from master...
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:--Quick Greenplum database status from Master instance only
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-----------------------------------------------------------
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-# of up segments, from configuration table     = 4
20170701:07:09:37:027224 gpstate:flash:dgadmin-[INFO]:-----------------------------------------------------------

postgres=# \l
                  List of databases
   Name    |  Owner  | Encoding |  Access privileges 
-----------+---------+----------+---------------------
 postgres  | dgadmin | UTF8     |
 template0 | dgadmin | UTF8     | =c/dgadmin         
                                : dgadmin=CTc/dgadmin
 template1 | dgadmin | UTF8     | =c/dgadmin         
                                : dgadmin=CTc/dgadmin
 tpch      | dgadmin | UTF8     |
 tpch_1g   | dgadmin | UTF8     |
(5 rows)

postgres=# select * from pg_database;
  datname  | datdba | encoding | datistemplate | datallowconn | datconnlimit | datlastsysoid | datfrozenxid | dattablespace | datconfig |              datacl             
-----------+--------+----------+---------------+--------------+--------------+---------------+--------------+---------------+-----------+----------------------------------
 tpch      |     10 |        6 | f             | t            |           -1 |         10898 |          888 |          1663 |           |
 postgres  |     10 |        6 | t             | t            |           -1 |         10898 |          888 |          1663 |           |
 tpch_1g   |     10 |        6 | f             | t            |           -1 |         10898 |          888 |          1663 |           |
 template1 |     10 |        6 | t             | t            |           -1 |         10898 |          888 |          1663 |           | {=c/dgadmin,dgadmin=CTc/dgadmin}
 template0 |     10 |        6 | t             | f            |           -1 |         10898 |          888 |          1663 |           | {=c/dgadmin,dgadmin=CTc/dgadmin}
(5 rows)