列出当前数据库所有表
dt
列出表名
SELECT tablename FROM pg_tables;
WHERE tablename NOT LIKE 'pg%'
AND tablename NOT LIKE 'sql_%'
ORDER BY tablename;
列出数据库名
l
或
SELECT datname FROM pg_database;
切换数据库
c 数据库名
1、通过命令行查询
d 数据库 —— 得到所有表的名字
d 表名 —— 得到表结构
2、通过SQL语句查询
"select * from pg_tables" —— 得到当前db中所有表的信息（这里pg_tables是系统视图）
"select tablename from pg_tables where schemaname='public'" —— 得到所有用户自定义表的名字（这里"tablename"字段是表的名字，"schemaname"是schema的名字。用户自定义的表，如果未经特殊处理，默认都是放在名为public的schema下）
General
copyright show PostgreSQL usage and distribution terms
g [FILE] or ; execute query (and send results to file or |pipe)
h [NAME] help on syntax of SQL commands, * for all commands
q quit psql
Query Buffer
e [FILE] [LINE] edit the query buffer (or file) with external editor
ef [FUNCNAME [LINE]] edit function definition with external editor
p show the contents of the query buffer
reset (clear) the query buffer
s [FILE] display history or save it to file
w FILE write query buffer to file
Input/Output
copy ... perform SQL COPY with data stream to the client host
echo [STRING] write string to standard output
i FILE execute commands from file
o [FILE] send all query results to file or |pipe
qecho [STRING] write string to query output stream (see o)
Informational
(options: S = show system objects, + = additional detail)
d[S+] list tables, views, and sequences
d[S+] NAME describe table, view, sequence, or index
da[S] [PATTERN] list aggregates
db[+] [PATTERN] list tablespaces
dc[S] [PATTERN] list conversions
dC [PATTERN] list casts
dd[S] [PATTERN] show comments on objects
ddp [PATTERN] list default privileges
dD[S] [PATTERN] list domains
det[+] [PATTERN] list foreign tables
des[+] [PATTERN] list foreign servers
deu[+] [PATTERN] list user mappings
dew[+] [PATTERN] list foreign-data wrappers
df[antw][S+] [PATRN] list [only agg/normal/trigger/window] functions
dF[+] [PATTERN] list text search configurations
dFd[+] [PATTERN] list text search dictionaries
dFp[+] [PATTERN] list text search parsers
dFt[+] [PATTERN] list text search templates
dg[+] [PATTERN] list roles
di[S+] [PATTERN] list indexes
dl list large objects, same as lo_list
dL[S+] [PATTERN] list procedural languages
dn[S+] [PATTERN] list schemas
do[S] [PATTERN] list operators
dO[S+] [PATTERN] list collations
dp [PATTERN] list table, view, and sequence access privileges
drds [PATRN1 [PATRN2]] list per-database role settings
ds[S+] [PATTERN] list sequences
dt[S+] [PATTERN] list tables
dT[S+] [PATTERN] list data types
du[+] [PATTERN] list roles
dv[S+] [PATTERN] list views
dE[S+] [PATTERN] list foreign tables
dx[+] [PATTERN] list extensions
l[+] list all databases
sf[+] FUNCNAME show a function's definition
z [PATTERN] same as dp
Formatting
a toggle between unaligned and aligned output mode
C [STRING] set table title, or unset if none
f [STRING] show or set field separator for unaligned query output
H toggle HTML output mode (currently off)
pset NAME [VALUE] set table output option
(NAME := {format|border|expanded|fieldsep|footer|null|
numericlocale|recordsep|tuples_only|title|tableattr|pager})
[on|off] show only rows (currently off)
T [STRING] set HTML <table> tag attributes, or unset if none
x [on|off] toggle expanded output (currently off)
Connection
c[onnect] {[DBNAME|- USER|- HOST|- PORT|-] | conninfo}
connect to new database (currently "postgres")
encoding [ENCODING] show or set client encoding
password [USERNAME] securely change the password for a user
conninfo display information about current connection
Operating System
cd [DIR] change the current working directory
iming [on|off] toggle timing of commands (currently off)
! [COMMAND] execute command in shell or start interactive shell
Variables
prompt [TEXT] NAME prompt user to set internal variable
set [NAME [VALUE]] set internal variable, or list all if no parameters
unset NAME unset (delete) internal variable
Large Objects
lo_export LOBOID FILE
lo_import FILE [COMMENT]
lo_list
lo_unlink LOBOID large object operations