SELECT h1.comments tabdesc,
h2.column_name columnname,
h2.data_type type,
h2.comments desci,
h2.data_length lenth,
h2.DATA_PRECISION PRECISION,
h2.Data_scale scale,
h2.NULLABLE isCannull
FROM (SELECT t1.table_name, t3.comments
FROM user_tables t1, user_tab_comments t3
WHERE t1.table_name = t3.table_name) h1,
(SELECT t2.table_name,
t2.column_name,
t2.data_type,
t2.Data_scale,
t2.DATA_PRECISION,
t2.data_length,
t2.NULLABLE,
t4.comments
FROM user_tab_columns t2, user_col_comments t4
WHERE t2.table_name = t4.table_name
AND t2.column_name = t4.column_name) h2
WHERE h1.table_name = h2.table_name
and h2.table_name = '表名'
根据表名查询表字段信息,字段为number类型,长度和精度由PRECISION和scale确定。