问题描述
我知道 PHP 和 MYSQL 在某种程度上已经解决了这个问题，但我想知道是否有人可以教我在 Oracle 10g(最好)和 11g 中将字符串(逗号分隔)拆分为多行的最简单方法.
I know this has been answered to some degree with PHP and MYSQL, but I was wondering if someone could teach me the simplest approach to splitting a string (comma delimited) into multiple rows in Oracle 10g (preferably) and 11g.
表格如下:
Name | Project | Error
108 test Err1, Err2, Err3
109 test2 Err1
我想创建以下内容:
Name | Project | Error
108 Test Err1
108 Test Err2
108 Test Err3
109 Test2 Err1
我已经看到了一些关于堆栈的潜在解决方案，但是它们只占一列(以逗号分隔的字符串).任何帮助将不胜感激.
I've seen a few potential solutions around stack, however they only accounted for a single column (being the comma delimited string). Any help would be greatly appreciated.
推荐答案
这可能是一种改进的方式(也可以使用 regexp 和 connect by):
This may be an improved way (also with regexp and connect by):
with temp as
(
select 108 Name, 'test' Project, 'Err1, Err2, Err3' Error from dual
union all
select 109, 'test2', 'Err1' from dual
)
select distinct
t.name, t.project,
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value)) as error
from
temp t,
table(cast(multiset(select level from dual connect by level <= length (regexp_replace(t.error, '[^,]+')) + 1) as sys.OdciNumberList)) levels
order by name
编辑:这是对查询的简单(如不深入")解释.
EDIT: Here is a simple (as in, "not in depth") explanation of the query.
length (regexp_replace(t.error, '[^,]+')) + 1使用regexp_replace删除任何不是分隔符的东西(这里的逗号)case) 和length +1来获取有多少元素(错误).select level from dual connect by level <= (...)使用分层查询来创建一个匹配数量不断增加的列发现，从 1 到错误总数.
length (regexp_replace(t.error, '[^,]+')) + 1usesregexp_replaceto erase anything that is not the delimiter (comma in this case) andlength +1to get how many elements (errors) are there.The
select level from dual connect by level <= (...)uses a hierarchical query to create a column with an increasing number of matches found, from 1 to the total number of errors.
预览:
select level, length (regexp_replace('Err1, Err2, Err3', '[^,]+')) + 1 as max
from dual connect by level <= length (regexp_replace('Err1, Err2, Err3', '[^,]+')) + 1
table(cast(multiset(.....) as sys.OdciNumberList)) 执行一些预言机类型的转换.cast(multiset(.....)) as sys.OdciNumberList将多个集合(原始数据集中的每一行一个集合)转换为单个数字集合 OdciNumberList.table()函数将集合转换为结果集.
table(cast(multiset(.....) as sys.OdciNumberList)) does some casting of oracle types.
- The
cast(multiset(.....)) as sys.OdciNumberListtransforms multiple collections (one collection for each row in the original data set) into a single collection of numbers, OdciNumberList. - The
table()function transforms a collection into a resultset.
FROM 没有连接会在您的数据集和多重集之间创建交叉连接.结果，数据集中有 4 个匹配项的行将重复 4 次(在名为column_value"的列中数字增加).
FROM without a join creates a cross join between your dataset and the multiset.
As a result, a row in the data set with 4 matches will repeat 4 times (with an increasing number in the column named "column_value").
预览:
select * from
temp t,
table(cast(multiset(select level from dual connect by level <= length (regexp_replace(t.error, '[^,]+')) + 1) as sys.OdciNumberList)) levels
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value)) 使用 column_value 作为 nth_appearance/regexp_substr 的 ocurrence 参数.t.name, t.project)以方便可视化.
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value)) uses the column_value as the nth_appearance/ocurrence parameter for regexp_substr.t.name, t.project as an example) for easy visualization.一些对 Oracle 文档的引用:
Some references to Oracle docs:
- REGEXP_REPLACE
- REGEXP_SUBSTR
- 可扩展性常量、类型和映射 (OdciNumberList)
- CAST(多组)
- 分层查询
这篇关于Oracle中将字符串拆分为多行的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持跟版网！