Oracle数据库查询表信息/列信息(列ID/列名/数据类型/长度/精度/是否可以为null/默认值/是否自增/是否是主键/列描述)

查询表信息（表名/表描述）

Select table_Name As Name,Comments As Value From User_Tab_Comments Where table_Type='TABLE' Order By table_Name Asc

查询列信息（列ID/列名/数据类型/长度/精度/是否可以为null/默认值/是否自增/是否是主键/列描述）

select a.COLUMN_ID As Colorder,a.COLUMN_NAME As ColumnName,a.DATA_TYPE As TypeName,b.comments As DeText,(Case When a.DATA_TYPE='NUMBER' Then a.DATA_PRECISION Else a.DATA_LENGTH End )As Length,a.DATA_SCALE As Scale,
(Case When (select Count(1)  from user_cons_columns aa, user_constraints bb where aa.constraint_name = bb.constraint_name 
 and bb.constraint_type = 'P' and aa.table_name = '表名' And aa.column_name=a.COLUMN_NAME)>0 Then 1 Else 0 End
 ) As IsPK,(
         case when (select count(1) from user_triggers tri INNER JOIN user_source src on tri.trigger_Name=src.Name 
            where (triggering_Event='INSERT' and table_name='表名')
        and regexp_like(text, concat(concat('nextvals+intos*?:s*?news*?.s*?',a.COLUMN_NAME),'s+?'),'i'))>0 
        then 1 else 0 end 
) As IsIdentity, 
    Case a.NULLABLE  When 'Y' Then 1 Else 0 End As CanNull,
    a.data_default As DefaultVal from user_tab_columns a Inner Join user_col_comments b On a.TABLE_NAME=b.table_name 
Where b.COLUMN_NAME= a.COLUMN_NAME   and a.Table_Name='表名'  order by a.column_ID Asc

　　　　　　注：查询包含了 判断列是否自增，查询相对比较慢。Oracle中暂时没有太好的方法 查询列是否自增，这里使用了Oracle的正则，如果有更好方法，欢迎 留言告知，相互学习！！