Oracle查询以获取列名 [英] Oracle query to fetch column names

问题描述

我有一个mySQL查询来从像这样的表中获取列:

I have a mySQL query to get columns from a table like this:

String sqlStr="select column_name 
from information_schema.COLUMNS 
where table_name='users' 
and table_schema='"+_db+"' 
and column_name not in ('password','version','id')"

如何在Oracle 11g数据库中更改以上查询?我需要获取列名作为表'users'的结果集，不包括某些列，并指定一个模式.现在我所有的表都在新表空间中，因此我可以指定表空间名称代替模式名称吗?

How do I change the above query in Oracle 11g database? I need to get columns names as a resultset for table 'users' excluding certain columns, specifying a schema. Right now I have all tables in my new tablespace, so do I specify tablespace name in place of schema name?

还为此提供通用的HQL吗?在我的新Oracle数据库(我是Oracle新手)中，我只有表空间名称，所以它等效于架构名称(在逻辑上?)

Also is there a generic HQL for this? In my new Oracle database (I am new to Oracle), I only have tablespace name, so is that equivalent to schema name (logically?)

推荐答案

对于当前用户拥有的表，information_schema.COLUMNS的Oracle等效值为USER_TAB_COLS，对于所有用户拥有的表，ALL_TAB_COLS或DBA_TAB_COLS等效.

The Oracle equivalent for information_schema.COLUMNS is USER_TAB_COLS for tables owned by the current user, ALL_TAB_COLS or DBA_TAB_COLS for tables owned by all users.

表空间不等同于架构，也不必提供表空间名称.

Tablespace is not equivalent to a schema, neither do you have to provide the tablespace name.

如果要查询ALL_TAB_COLS或DBA_TAB_COLS特定用户拥有的OF列的列，则提供架构/用户名将很有用.在您的情况下，我想查询将类似于:

Providing the schema/username would be of use if you want to query ALL_TAB_COLS or DBA_TAB_COLS for columns OF tables owned by a specific user. in your case, I'd imagine the query would look something like:

String sqlStr= "
SELECT column_name
  FROM all_tab_cols
 WHERE table_name = 'USERS'
   AND owner = '" +_db+ "'
   AND column_name NOT IN ( 'PASSWORD', 'VERSION', 'ID' )"

请注意，使用这种方法会冒着SQL注入的风险.

Note that with this approach, you risk SQL injection.

编辑:表名和列名大写，因为它们在Oracle中通常是大写的.如果使用双引号将它们引起来，则它们仅是小写或混合大小写.

Uppercased the table- and column names as these are typically uppercase in Oracle; they are only lower- or mixed case if created with double quotes around them.

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