Greenplum 6.x common statements

One . Create directory

root Users log in to four servers , Each machine performs the following operations

[[email protected] tmp]# mkdir -p /datax/tbs_tmp
[[email protected] tmp]# mkdir -p /datax/tbs_tmp2
#  Grant authority 
[[email protected] tmp]# chown gpadmin:gpadmin /datax/*

Two . Create a library

Create a library

gpadmin The user login master machine

[[email protected] ~]$ psql -d postgres
psql (9.4.24)
Type "help" for help.
postgres=# create database gpdb encoding='UTF8';
CREATE DATABA
gpdb=# SELECT datname from pg_database;
  datname
-----------
 template1
 template0
 postgres
 gpperfmon
 gpdb
(5 rows)

postgres=# \q

3、 ... and . Table space

gpadmin The user login master machine

Every Greenplum Database systems have the following default table spaces .

pg_global For sharing system directories .
pg_default, Default tablespace . from template1 and template0 Database usage .
These tablespaces use the default system location , That is, the location of the data directory created during system initialization .

To view tablespace information , Please use pg_tablespace The table of contents gets the object of the table space ID（OID）, And then use gp_tablespace_location() Function to display the table space directory . This is an example of listing a user-defined table space myspace：

[[email protected] tmp]# su - gpadmin
#  Get into gpdb library 
[[email protected] ~]$ psql -d gpdb
psql (9.4.24)
Type "help" for help.

#  Create tablespace 
gpdb=# create tablespace tbs_tmp location '/datax/tbs_tmp';
CREATE TABLESPACE
gpdb=# create tablespace tbs_tmp2 location '/datax/tbs_tmp2';
CREATE TABLESPACE
gpdb=#
##########################  View tablespaces  #####################
gpdb=# SELECT oid, * FROM pg_tablespace ;
  oid  |  spcname   | spcowner |               spcacl                | spcoptions
-------+------------+----------+-------------------------------------+------------
  1663 | pg_default |       10 |                                     |
  1664 | pg_global  |       10 |                                     |
 16658 | tbs_tmp2   |       10 |                                     |
 16657 | tbs_tmp    |       10 | {
    gpadmin=C/gpadmin,guser=C/gpadmin} |
(4 rows)

# Table space  OID myspace yes 16657 .  function gp_tablespace_location() To display the tablespace location of the system consisting of two segment instances and the primary instance 
gpdb=# SELECT * FROM gp_tablespace_location(16657);
 gp_segment_id |   tblspc_loc
---------------+----------------
             0 | /datax/tbs_tmp
             7 | /datax/tbs_tmp
             2 | /datax/tbs_tmp
             4 | /datax/tbs_tmp
             1 | /datax/tbs_tmp
             6 | /datax/tbs_tmp
             5 | /datax/tbs_tmp
             3 | /datax/tbs_tmp
            -1 | /datax/tbs_tmp
(9 rows)

gpdb=#

# This query uses gp_tablespace_location() Catalog gp_segment_configuration Table to display segment instance information and myspace File system location of the tablespace .

gpdb=# WITH spc AS (SELECT * FROM gp_tablespace_location(16657)) SELECT seg.role, spc.gp_segment_id as seg_id, seg.hostname, seg.datadir, tblspc_loc FROM spc, gp_segment_configuration AS seg WHERE spc.gp_segment_id = seg.content ORDER BY seg_id;
 role | seg_id | hostname |        datadir        |   tblspc_loc
------+--------+----------+-----------------------+----------------
 p    |     -1 | mdw      | /datax/master/gpseg-1 | /datax/tbs_tmp
 m    |     -1 | smdw     | /datax/master/gpseg-1 | /datax/tbs_tmp
 p    |      0 | sdw1     | /datax/primary/gpseg0 | /datax/tbs_tmp
 m    |      0 | sdw2     | /datax/mirror/gpseg0  | /datax/tbs_tmp
 m    |      1 | sdw2     | /datax/mirror/gpseg1  | /datax/tbs_tmp
 p    |      1 | sdw1     | /datax/primary/gpseg1 | /datax/tbs_tmp
 m    |      2 | sdw2     | /datax/mirror/gpseg2  | /datax/tbs_tmp
 p    |      2 | sdw1     | /datax/primary/gpseg2 | /datax/tbs_tmp
 p    |      3 | sdw1     | /datax/primary/gpseg3 | /datax/tbs_tmp
 m    |      3 | sdw2     | /datax/mirror/gpseg3  | /datax/tbs_tmp
 m    |      4 | sdw1     | /datax/mirror/gpseg4  | /datax/tbs_tmp
 p    |      4 | sdw2     | /datax/primary/gpseg4 | /datax/tbs_tmp
 p    |      5 | sdw2     | /datax/primary/gpseg5 | /datax/tbs_tmp
 m    |      5 | sdw1     | /datax/mirror/gpseg5  | /datax/tbs_tmp
 m    |      6 | sdw1     | /datax/mirror/gpseg6  | /datax/tbs_tmp
 p    |      6 | sdw2     | /datax/primary/gpseg6 | /datax/tbs_tmp
 m    |      7 | sdw1     | /datax/mirror/gpseg7  | /datax/tbs_tmp
 p    |      7 | sdw2     | /datax/primary/gpseg7 | /datax/tbs_tmp
(18 rows)

gpdb=#

Specify tablespace

SET default_tablespace = tbs_tmp;
CREATE TABLE foo(i int);

gpdb=# SET default_tablespace = tbs_tmp;
SET
gpdb=# CREATE TABLE foo(i int);
NOTICE:  Table doesn't have 'DISTRIBUTED BY' clause -- Using column named 'i' as the Greenplum Database data distribution key for this table. HINT: The 'DISTRIBUTED BY' clause determines the distribution of data. Make sure column(s) chosen are the optimal data distribution key to minimize skew.
CREATE TABLE
gpdb=#

Delete tablespace

Be careful ： If the table space is not empty or stores temporary files or transaction files , The tablespace cannot be deleted .

The tablespace owner or superuser has permission to delete tablespaces . Before deleting all objects in the database that use this tablespace , You cannot delete this tablespace .

DROP TABLESPACE xxx

Four . Create and manage patterns schema

establish schema

gpdb=# create schema tmp_schema;
CREATE SCHEMA

To create or access objects in a schema , Write a qualified name consisting of schema name and table name , And separated by a period . for example

myschema.table

for example , You can create patterns owned by others , To limit user activity to a well-defined namespace

CREATE SCHEMA schemaname AUTHORIZATION username;

5、 ... and . User roles

User level roles are considered database roles that can log in to the database and initiate database sessions . therefore , When you use this command to create a new user level role CREATE ROLE, You must specify LOGIN jurisdiction . for example ：

CREATE ROLE jsmith WITH LOGIN;

Create the role

# guser No login rights 
gpdb=# create ROLE guser password 'guser';
NOTICE:  resource queue required -- using default resource queue "pg_default"
CREATE ROLE
gpdb=# grant all on database gpdb to guser;
GRANT
#  Have login permission 
gpdb=# create ROLE guser2 WITH LOGIN password 'guser2';
NOTICE:  resource queue required -- using default resource queue "pg_default"
CREATE ROLE
gpdb=#

Modify the permissions

ALTER ROLE username WITH PASSWORD ‘passwd123’;
ALTER ROLE admin VALID UNTIL ‘infinity’;
ALTER ROLE username LOGIN;
ALTER ROLE username RESOURCE QUEUE que1;
ALTER ROLE username DENY DAY ‘Sunday’;

Role members

It is usually convenient to group users together to simplify the management of object permissions ： such , You can grant or revoke permissions to an entire group .

CREATE ROLE admin CREATEROLE CREATEDB;

GRANT After the group role exists , You can use andREVOKE Command to add and remove members （ User roles ）

GRANT admin TO user1, user2;
REVOKE admin FROM user3;

To manage object permissions , You will only grant appropriate permissions to group level roles , Then the member user role inherits the object permissions of the group role .

GRANT ALL ON TABLE mytable TO admin;
GRANT ALL ON SCHEMA myschema TO admin;
GRANT ALL ON DATABASE mydb TO admin;

Be careful ：
Character attributes LOGIN, SUPERUSER, CREATEDB, CREATEROLE,CREATEEXTTABLE and RESOURCE QUEUE It will never be inherited like the normal permissions of database objects .

User members must actually SET ROLE Only a specific role with one of these attributes can use this attribute

SET ROLE admin;

for example

gpdb=# ALTER ROLE guser2 SUPERUSER LOGIN CREATEDB;
ALTER ROLE
gpdb=#

6、 ... and . Grant authority

#  Grant tablespace permissions to guser
gpdb=# GRANT CREATE ON TABLESPACE tbs_tmp TO guser;
GRANT

7、 ... and . Create table

CREATE TABLE foo(i int) TABLESPACE tbs_tmp;

8、 ... and . Remote login

Modify file

[[email protected] ~]$ vi /datax/master/gpseg-1/pg_hba.conf

#  add to the content 
host     all         guser2      0.0.0.0/0       trust

Make configuration effective

[[email protected] ~]$ gpstop -u
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Starting gpstop with args: -u
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Gathering information and validating the environment...
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Obtaining Greenplum Master catalog information
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Obtaining Segment details from master...
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Greenplum Version: 'postgres (Greenplum Database) 6.18.2 build commit:1242aadf0137d3b26ee42c80e579e78bd7a805c7'
20220703:22:21:58:123477 gpstop:mdw:gpadmin-[INFO]:-Signalling all postmaster processes to reload
.
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:---------------------------------------------
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:-Some segment postmasters were not reloaded
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:---------------------------------------------
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:-   Host   Datadir                 Port   Status
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:-   smdw   /datax/master/gpseg-1   5432   u
20220703:22:21:59:123477 gpstop:mdw:gpadmin-[INFO]:---------------------------------------------
[[email protected] ~]$

Invalid login

Re execution of the following is invalid

[[email protected] ~]$ pg_ctl reload -D /datax/master/gpseg-1/
server signaled
[[email protected] ~]$

usage: Use tablespaces to store database objects

# Users with tablespace permissions CREATE You can create database objects in this tablespace , Such as table 、 Index and database 
#  Format ：CREATE TABLE tablename(options) TABLESPACE spacename;
# In tablespace space1 Create a table in 
CREATE TABLE foo(i int) TABLESPACE tbs_tmp;
# You can also use this parameter for commands that do not specify a tablespace default_tablespace Specify the default table space ：CREATE TABLECREATE INDEX
SET default_tablespace = space1;
CREATE TABLE foo(i int);

Test data

gpadmin user

[[email protected] ~]$ psql -d gpdb
psql (9.4.24)
Type "help" for help.

gpdb=# SET default_tablespace = tbs_tmp;
SET
gpdb=# CREATE TABLE foo(i int);
NOTICE:  Table doesn't have 'DISTRIBUTED BY' clause -- Using column named 'i' as the Greenplum Database data distribution key for this table. HINT: The 'DISTRIBUTED BY' clause determines the distribution of data. Make sure column(s) chosen are the optimal data distribution key to minimize skew.
CREATE TABLE
gpdb=#
#  Insert 16 Data 
gpdb=# insert into foo values(100000);
INSERT 0 

Add data

gpdb=# select count(*) from foo;
  count
---------
 4854608
(1 row)

Initial data foo surface 16 strip , foo2 by 0 strip .
insert The data volume is as follows

Change in size



master Nodes have tbs_tmp Catalog

sdw2 Of gpseg0

The final size comparison

state