1.歷史命令與補全功能
可以使用上下鍵把以前使用過的命令或SQL語句調出來。
連續按兩個tab鍵表示命令補全或者提示輸入。--類似於Linux功能

2.自動提交方面的技巧
在psql中，事務是自動提交的。（與oracle不同）
如果不想自動提交，可以：
    預設，postgresql是自動提交的，可以避免自動提交 
    1）使用begin;命令 
      示例： 
    postgres=# begin; 
    BEGIN 
    postgres=# insert into test values(2,2); 
    INSERT 0 1 
    postgres=# select * from test; 
     id | name 
    ----+------ 
      1 | 
      1 |    2 
      2 |    2 
    (3 行記錄) 


    postgres=# rollback; 
    ROLLBACK 
    postgres=# select * from test; 
     id | name 
    ----+------ 
      1 | 
      1 |    2 
    (2 行記錄) 

    2）還可以直接關閉自動提交的功能 
    \set AUTOCOMMIT off  --注意，AUTOCOMMIT要大寫。
    示例： 
    postgres=# \set AUTOCOMMIT off 
    postgres=# 
    postgres=# 
    postgres=# insert into test values(2,2); 
    INSERT 0 1 
    postgres=# select * from test; 
     id | name 
    ----+------ 
      1 | 
      1 |    2 
      2 |    2 
    (3 行記錄) 


    postgres=# rollback; 
    ROLLBACK 
    postgres=# select * from test; 
     id | name 
    ----+------ 
      1 | 
      1 |    2 
    (2 行記錄)

3.得到psql命令列中具體執行的SQL語句
啟動psql時加上-E引數，或者在命令列中使用\set ECHO_HIDDEN on|off命令。
[
 
[email protected] ~]$ psql -E
psql (9.6.1)
Type "help" for help.

postgres=# \d
********* QUERY **********
SELECT n.nspname as "Schema",
  c.relname as "Name",
  CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'm' THEN 'materialized view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' END as "Type",
  pg_catalog.pg_get_userbyid(c.relowner) as "Owner"
FROM pg_catalog.pg_class c
     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','v','m','S','f','')
      AND n.nspname <> 'pg_catalog'
      AND n.nspname <> 'information_schema'
      AND n.nspname !~ '^pg_toast'
  AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************

        List of relations
 Schema | Name | Type  |  Owner   
--------+------+-------+----------
 public | test | table | postgres
 public | txx  | table | postgres
(2 rows)

postgres=# \set ECHO_HIDDEN off
postgres=# \d
        List of relations
 Schema | Name | Type  |  Owner   
--------+------+-------+----------
 public | test | table | postgres
 public | txx  | table | postgres
(2 rows)

postgres=# \set ECHO_HIDDEN on
postgres=# \d
********* QUERY **********
SELECT n.nspname as "Schema",
  c.relname as "Name",
  CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'm' THEN 'materialized view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' END as "Type",
  pg_catalog.pg_get_userbyid(c.relowner) as "Owner"
FROM pg_catalog.pg_class c
     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','v','m','S','f','')
      AND n.nspname <> 'pg_catalog'
      AND n.nspname <> 'information_schema'
      AND n.nspname !~ '^pg_toast'
  AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************

        List of relations
 Schema | Name | Type  |  Owner   
--------+------+-------+----------
 public | test | table | postgres
 public | txx  | table | postgres
(2 rows)