在日常使用oracle的過程中，我們需要經常關注的oralce最大連線數、併發連線數、當前連線數、使用者系統許可權等等，涉及的統計很多很多，但是有時候確實很難記住，因此在這裡做乙個備註。
1、查詢oracle的連線數
select count(*) from v$session;select count(*) from v$session where status='active';select count(*) from v$process;select value from v$parameter where name = 'processes';select username,count(username) from v$session where username is not null group by username;select username,osuser,status,schemaname,machine from v$session
where username is not null and username = 'mobil' order by username,osuser;
select * from all_users;select * from dba_sys_privs;
select * from user_sys_privs;
select * from role_sys_privs;select * from dba_tab_privs;
select * from all_tab_privs;
select * from user_tab_privs;
select * from dba_roles;select * from dba_role_privs;
select * from user_role_privs;
select * from v$pwfile_users;select b.sid, b.serial#, spid, b.username, paddr, sql_text, b.machine, logon_time
from v$process a, v$session b, v$sqlarea c
where a.addr = b.paddr and b.sql_hash_value = c.hash_value
order by b.sid,b.serial#,spid
alter system kill session 'sid, serial#';-- 查詢當前使用者下所有表 --
select * from user_tables;
-- 查詢使用者有所表下字段資訊 --
select * from user_tab_columns;
-- 查詢使用者所有字段資訊的注釋 --
select * from user_col_comments;
-- 查詢使用者字段約束和字段對應關係 --
select * from user_cons_columns;
-- 查詢使用者所有約束資訊 --
select * from user_constraints;
-- 查詢全部表和對應表結構 --
select
t.database_name as database_name,
t.table_name as table_name,
t.column_name as column_name,
t.column_type as column_type,
t.data_length as data_length,
t.column_comment as column_comment,
b.constraint_type as constraint_type
from
( select
ub.tablespace_name as database_name,
utc.table_name as table_name,
utc.column_name as column_name,
utc.data_type as column_type,
utc.data_length as data_length,
ucc.comments as column_comment
from
user_tables ub
left join user_tab_columns utc on ub.table_name = utc.table_name
left join user_col_comments ucc on utc.column_name = ucc.column_name
and utc.table_name = ucc.table_name
) tleft join (
select
ucc.table_name as table_name,
ucc.column_name as column_name,
wm_concat ( uc.constraint_type ) as constraint_type
from
user_cons_columns ucc
left join user_constraints uc on ucc.constraint_name = uc.constraint_name
group by
ucc.table_name,
ucc.column_name
) b on t.table_name = b.table_name
and t.column_name = b.column_name
如有不當之處，請及時指出，謝謝！
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