`psql` 扩展模式等效于 `mysql`

178*_*024 5 mysql postgresql command-line-interface psql echo

我对以下事情感到沮丧:

0:33:1407402356:root@ahost:~# echo 'use wordpress_3_6_1; select * from wp_posts;'
 | mysql -u mysqluser -pmysqlpasswdord | wc -l -L
42   40585
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SQL 查询结果被破坏得很丑陋。

PostgreSQLpsql提供了 helper 特性扩展模式。看看它在行动:

postgres@ahost:~$ echo '\c openerp7-0 \\ select * from pg_shadow' | psql
You are now connected to database "openerp7-0" as user "postgres".
 usename  | usesysid | usecreatedb | usesuper | usecatupd | userepl |          
   passwd                | valuntil | useconfig 
----------+----------+-------------+----------+-----------+---------+----------
-------------------------+----------+-----------
 openerp |    16384 | t           | t        | t         | t       | 
ahash |          | 
 postgres |       10 | t           | t        | t         | t       | 
anotherhash |          | 
(2 rows)

postgres@ahost:~$ echo '\c openerp7-0 \\ \x \\ select * from pg_shadow' |
psql                
You are now connected to database "openerp7-0" as user "postgres".
Expanded display is on.
-[ RECORD 1 ]------------------------------------
usename     | openerp
usesysid    | 16384
usecreatedb | t
usesuper    | t
usecatupd   | t
userepl     | t
passwd      | ahash
valuntil    | 
useconfig   | 
-[ RECORD 2 ]------------------------------------
usename     | postgres
usesysid    | 10
usecreatedb | t
usesuper    | t
usecatupd   | t
userepl     | t
passwd      | anotherhash
valuntil    | 
useconfig   |
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对于包含列的表,这种扩展模式很可爱:

postgres@ahost:~$ echo '\c openerp7-0 \\ \x \\ select * from res_partner' |
psql | wc -l -L
223   44423
postgres@ahost:~$ echo '\c openerp7-0 \\ select * from res_partner' | psql |
wc -l -L
  9   94030
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当然,那只是当人们不介意把排数弄乱的时候wc -l

人们如何完成mysql类似于 中的扩展模式的功能psql

小智 8

如果我正确理解您想要实现的目标,您可以尝试使用 \G 分隔符(而不是分号),如下所示:

echo 'SELECT * FROM mytable\G' | mysql -u myuser -p mypassword mydb
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示例输出:

*************************** 1. row ***************************
    id: 1
locale: de
  name: Afghanistan
*************************** 2. row ***************************
    id: 2
locale: de
  name: Ägypten
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