[英]SQL Server 2014 equivalent to mysql's find_in_set()
I'm working with a database that has a locations table such as: 我正在使用具有位置表的数据库,例如:
locationID | locationHierarchy
1 | 0
2 | 1
3 | 1,2
4 | 1
5 | 1,4
6 | 1,4,5
which makes a tree like this 像这样的树
1
--2
----3
--4
----5
------6
where locationHierarchy is a csv string of the locationIDs of all its ancesters (think of a hierarchy tree). 其中locationHierarchy是其所有祖先的locationID的csv字符串(以层次结构树为例)。 This makes it easy to determine the hierarchy when working toward the top of the tree given a starting locationID.
在给定起始locationID的情况下,在朝树的顶部工作时,可以轻松确定层次结构。
Now I need to write code to start with an ancestor and recursively find all descendants. 现在,我需要编写代码以始祖,并递归地找到所有后代。 MySQL has a function called 'find_in_set' which easily parses a csv string to look for a value.
MySQL具有一个名为“ find_in_set”的函数,该函数可以轻松解析csv字符串以查找值。 It's nice because I can just say "find in set the value 4" which would give all locations that are descendants of locationID of 4 (including 4 itself).
很好,因为我可以说“找到设置值4”,这将给出locationID为4的后代(包括4本身)的所有位置。
Unfortunately this is being developed on SQL Server 2014 and it has no such function. 不幸的是,这是在SQL Server 2014上开发的,没有任何功能。 The CSV string is a variable length (virtually unlimited levels allowed) and I need a way to find all ancestors of a location.
CSV字符串的长度是可变的(几乎允许无限制的级别),我需要一种方法来查找某个位置的所有祖先。
A lot of what I've found on the internet to mimic the find_in_set function into SQL Server assumes a fixed depth of hierarchy such as 4 levels maximum) which wouldn't work for me. 我在互联网上发现的许多将find_in_set函数模仿到SQL Server的功能都假定了固定的层次结构深度(例如最多4个级别),这对我不起作用。
Does anyone have a stored procedure or anything that I could integrate into a query? 是否有人有存储过程或我可以集成到查询中的任何内容? I'd really rather not have to pull all records from this table to use code to individually parse the CSV string.
我真的希望不必从该表中提取所有记录来使用代码分别解析CSV字符串。
I would imagine searching the locationHierarchy string for locationID% or %,{locationid},% would work but be pretty slow. 我可以想象在locationHierarchy字符串中搜索locationID%或%,{locationid},%会起作用,但是速度很慢。
I think you want like
-- in either database. 我想你想要
like
-任一数据库。 Something like this: 像这样:
select l.*
from locations l
where l.locationHierarchy like @LocationHierarchy + ',%';
If you want the original location included, then one method is: 如果要包括原始位置,则一种方法是:
select l.*
from locations l
where l.locationHierarchy + ',' like @LocationHierarchy + ',%';
I should also note that SQL Server has proper support for recursive queries, so it has other options for hierarchies apart from hierarchy trees (which are still a very reasonable solution). 我还应注意,SQL Server对递归查询提供了适当的支持,因此它除了层次结构树以外,还为层次结构提供了其他选择(这仍然是一个非常合理的解决方案)。
Finally It worked for me.. 终于对我有用。
SELECT * FROM locations WHERE locationHierarchy like CONCAT(@param,',%%') OR
o.unitnumber like CONCAT('%%,',@param,',%%') OR
o.unitnumber like CONCAT('%%,',@param)
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