g******g
发帖数: 35 | 1 请提供你的联系方式： name and e-mail address
A HIGH-PERFORMANCE SCHEDULER FOR JOIN
QUERIES EXECUTION OVER GRID-AWARE
ARCHITECTURES
Abstract
A Grid is a collection of computing resources that share and perform tasks.
Performance optimization can be achieved by
exploiting the Grid power utilities; i.e. multi-processing, multi-
programming, abstract task execution. This paper explores
the management of distributed relational databases over Grid infrastructures
for the execution of J − join queries. Our... 阅读全帖 |
|
s**********o
发帖数: 14359 | 2 【 以下文字转载自 Dreamer 讨论区 】
发信人: Dreamer (不要问我从哪里来), 信区: Dreamer
标 题: A SQL query never stop running is bothering me: help needed!
关键字: SQL
发信站: BBS 未名空间站 (Thu Oct 18 15:02:34 2012, 美东)
Just now I issued a query to update a column's value.
The table is really big so it never stop running.
After waited for 40 minutes I tried to give up, so I canceled my query.
But what happening now is I can't query this table, all related queries will
hang there running.
And I can't detach the database and re attac... 阅读全帖 |
|
p****e
发帖数: 165 | 3 在MySQL中如何做query tuning? 就是优化query plan. Document里说是用EXPLAIN来
optimize query. 但如何看query plan的结果呢？比如我有几百行的sql queries, 运
行需要花10分钟得到结果，那么用EXPLAIN看query plan之后，有看哪些方面去优化呢？
谢谢！ |
|
p****e
发帖数: 165 | 4 在MySQL中如何做query tuning? 就是优化query plan. Document里说是用EXPLAIN来
optimize query. 但如何看query plan的结果呢？比如我有几百行的sql queries, 运
行需要花10分钟得到结果，那么用EXPLAIN看query plan之后，有看哪些方面去优化呢？
谢谢！ |
|
l******9
发帖数: 579 | 5 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: SQL server optimal query design
发信站: BBS 未名空间站 (Fri Jul 4 12:54:15 2014, 美东)
I need do some SQL server query design.
For doing the same query, there may be many different kinds of query design.
But, I need to learn which kinds of query design/implementation are optimal
for performance.
Could anybody recommend some books/publications to learn how to do that ?
Any help would be appreciated. |
|
b**********5
发帖数: 7881 | 6 如果我现在有一个system，
把data 用json或者protobuf tobyte 后， 按照unique id， 和那个protobuf/json存
入nosql后， 有什么好的东西去do custom query？
mangodb， Cassandra, 有什么高效的query？如果说， 我这个queries， 提前不不知
道customer会有什么query pattern， 什么field都能去query |
|
p*********a
发帖数: 61 | 7 My application has a form to collect users' inputs, which are passed to a
parameterized SQL query over a table. When a user skips some boxes in the
form, the query should have no predicates on the corresponding attributes.
An extreme case is if the user inputs nothing, the query should return the
entire table.
My question is if the parameterized query is prefixed, what values are
supposed to be used for the parameters whose boxes are empty?
I understand that there are some solutions to work arou... 阅读全帖 |
|
l******9
发帖数: 579 | 8 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: SQL server optimal query design
发信站: BBS 未名空间站 (Fri Jul 4 12:54:15 2014, 美东)
I need do some SQL server query design.
For doing the same query, there may be many different kinds of query design.
But, I need to learn which kinds of query design/implementation are optimal
for performance.
Could anybody recommend some books/publications to learn how to do that ?
Any help would be appreciated. |
|
|
l******9
发帖数: 579 | 9 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: SQL server optimal query design
发信站: BBS 未名空间站 (Fri Jul 4 12:54:15 2014, 美东)
I need do some SQL server query design.
For doing the same query, there may be many different kinds of query design.
But, I need to learn which kinds of query design/implementation are optimal
for performance.
Could anybody recommend some books/publications to learn how to do that ?
Any help would be appreciated. |
|
t***q
发帖数: 418 | 10 【 以下文字转载自 Programming 讨论区 】
发信人: treeq (treeq), 信区: Programming
标 题: 问一个如何建立一个rest web service ,其中有query string 功能。
发信站: BBS 未名空间站 (Wed Mar 4 21:28:13 2015, 美东)
如题，要建一个 web service， 有 query string 的功能。主要是，有一个 影视作品
的title 进来，用 web service 里的 一些function, 和已有的一个 flat file, 那个
flat file里，有许多影视作品的 title , 及其他一些信息， 用这个 flat file, 和
已输入的 title, 算出与之最相似的影视作品的title, 然后 call 相关 url 后， 能
有一个 hash table 输出， 其中有最相近的 title ， 和 相似率， 一个类似
confidence level 的东西。
例子如下：
http://www.dreamsyssoft.com/python-scriptin... 阅读全帖 |
|
t***q
发帖数: 418 | 11 【 以下文字转载自 Programming 讨论区 】
发信人: treeq (treeq), 信区: Programming
标 题: 问一个如何建立一个rest web service ,其中有query string 功能。
发信站: BBS 未名空间站 (Wed Mar 4 21:28:13 2015, 美东)
如题，要建一个 web service， 有 query string 的功能。主要是，有一个 影视作品
的title 进来，用 web service 里的 一些function, 和已有的一个 flat file, 那个
flat file里，有许多影视作品的 title , 及其他一些信息， 用这个 flat file, 和
已输入的 title, 算出与之最相似的影视作品的title, 然后 call 相关 url 后， 能
有一个 hash table 输出， 其中有最相近的 title ， 和 相似率， 一个类似
confidence level 的东西。
例子如下：
http://www.dreamsyssoft.com/python-scriptin... 阅读全帖 |
|
w******i
发帖数: 1476 | 12 error message: invalid operation
我做了一个简单query, 数据是based on以前两个queries(subqueries)的results. 格式
很简单, 大概是:
SELECT SUBQUERYTABLE1.*, SUBQUERYTABLE2.*
FROM SUBQUERYTABLE1 LEFT JOIN SUBQUERYTABLE2
ON SUBQUERYTABLE1.PERSON_ID=SUBQUERYTABLE1.PERSON_ID;
前两天这个query一直都run得好好的, 今天在其中一个subquery里加了一个field,
subqueries都正常运行, 可是最后一个query却出现"Invalid Operation"
VB有check过,都有必需的references...
希望我把事情说清楚了. 到底是什么原因? 有没有人知道? 万分感谢! |
|
c*****r
发帖数: 4 | 13 【 以下文字转载自 JobHunting 讨论区,原文如下 】
发信人: Carrier (Enterprise), 信区: JobHunting
标 题: 求教数据库的query optimization 工作的面试
发信站: Unknown Space - 未名空间 (Wed Jun 9 22:13:13 2004) WWW-POST
各位数据库高手, 能不能指点一下会问什么? 有六个人面试, 每人半小时.
他们都精通Query optimization, 工作是数据库地层的query 的优化(不是DBA, 或数据库
应用). 我这方面经验也不多. 他们大致会问什么呢? 数据库基本知识? indexing, b
tree? C coding? Data Structure? Algorithm? Different Query algorithms? SQL? 东
西太多, 也很茫然, 希望能得到点指点. 多谢多谢!!!! |
|
j*****n
发帖数: 1781 | 14 今儿我们组里的一哥们遇到一个奇怪的现象：
在query analyzer 里面运行一个query,花了15分钟得到结果，
然后放到把这个query做成一个stored procedure， 除了把where 里面的条件换成了变
量而已，结果需要30分钟才行。
我们的环境是用local的query analyzer 连到 DB server 上。
为什么会有这么大的区别呢？ |
|
h***a
发帖数: 18 | 15 Table:
ID Time Event
1001 01/01/2010 0
1001 02/01/2010 0
1001 03/01/2010 1
1001 04/01/2010 1
1001 05/01/2010 1
1001 06/01/2010 0
1001 07/01/2010 0
1002 01/01/2010 0
1002 02/01/2010 1
1002 03/01/2010 1
1002 04/01/2010 0
1002 05/01/2010 1
1002 06/01/2010 1
1002 07/01/2010 1
1002 08/01/2010 0
1003 01/01/2010 0
1003 02/01/2010 0
1003 03/01/2010 0
1003 04/01/2010 1
1003 05/01/2010 1
1003 06/01/2010 1
1004 01/01/2010 0
1004 02/01/2010 0
1004 03/... 阅读全帖 |
|
i****a
发帖数: 36252 | 16 Let's say I have a query like this:
Select *
from TableA
where ColA >
(
Select colX
from TableY
where colZ = 'xxx'
)
How do I write it so when the sub query does not return any result, the main
query would use a predefined lookup value?
end result like this if the sub query returns no records:
Select *
from TableA
where ColA > 1 |
|
s***s
发帖数: 1301 | 17 这两天check 一个t-sql query,发现这个query总是选择不是最优的index，
如果指定最优的index，performance就会好很多。但是我们不想在query里这么做（
with
index = ....)，这个query是production的code, 将来万一改变index,可能会导致
performance变动，增加维护工作困难。
不知道是什么原因sql server为什么总是不能选择最优index， 是plan被cached了吗？
有什么方法可以让sql server更新它的plan呢？ |
|
p**********e
发帖数: 316 | 18 有好几个SQL常见的问题
1) table variable 不支持 index, 基本上是table scan
2) temp table 没有PK
3） 尽量避免loop, 你可以在temp table里多设置几个column 储存中间值， 尽量用
query解决问题， query是batch processing， 当然并不一限于一个query
4） 还有一些其他的query写法，根据你的data volumn来优化，比如你知道要实际要处
理的量不太多，你可以先find out这些records, 即使用table variable 你也只需要
scan一次了 |
|
l******9
发帖数: 579 | 19 I need do some SQL server query design.
For doing the same query, there may be many different kinds of query design.
But, I need to learn which kinds of query design/implementation are optimal
for performance.
Could anybody recommend some books/publications to learn how to do that ?
Any help would be appreciated. |
|
s*****n
发帖数: 2174 | 20 用readLines读入.
比如你的SQL query在一个叫做test.sql的file里面, 内容是
SELECT COUNT(*)
FROM my_table;
在R里面
> sql.query <- paste(readLines("test.sql"), collapse = " ")
> sql.query
[1] "SELECT COUNT(*) FROM my_table;"
然后就随你怎么用sql.query这个string了. |
|
c***y
发帖数: 560 | 21 似乎rabin-karp对固定一样长度的query集支持比较好，
如果query集里的query不定长度呢？还可以实现o(n)吗?
谢谢 |
|
w****x
发帖数: 2483 | 22
比如找top 10 queries, 把大文件hash分成200个小文件, 每个小文件可以放入内存.
每个小文件取top 5 queries, 从1000个query中找出前10个, 除非很巧, 基本可以得出
top 10 |
|
l******9
发帖数: 579 | 23 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: change year format in Access by SQL query
发信站: BBS 未名空间站 (Mon Oct 13 12:50:53 2014, 美东)
I am working on Access 2012 on win 7. In a table, I need to change a year
date format from '1-Jan-06' to 2006 and from '1-Jan-90' to 1990. I only need
year.
This is my query
SELECT *,
CASE
WHEN CAST(right(year_date,2) , INT) <= 12
THEN 2000 + CAST(right(year_date,2) , INT)
ELSE 1900 + CAST(right(year_date,2) , INT)
END
FROM my_table;
I ... 阅读全帖 |
|
a********8
发帖数: 1625 | 24 第一步是计算query point到root1的距离，把它作为best_value,然后搜索root1的两边
,此时不能排除右边。
先搜左边，发现query point到root2的距离更小，update,但是并不能小于query point
到root1所划分的分割线，所有root1的右边还得接着搜（否则可以直接扔掉右边）
这样可以达到LogN的时间复杂度 |
|
q****x
发帖数: 7404 | 25 【 以下文字转载自 JobHunting 讨论区 】
发信人: quantx (X矿工), 信区: JobHunting
标 题: MySQL如何查看query执行时间？
发信站: BBS 未名空间站 (Sat Dec 22 19:34:09 2012, 美东)
命令行下，每次手动执行query后能自动显示这次query用多少时间。 |
|
h*****l
发帖数: 184 | 26 【 以下文字转载自 shopping 讨论区,原文如下 】
发信人: hanibal (汉尼拔), 信区: shopping
标 题: ASP的script function里, 可以query database吗?
发信站: The unknown SPACE (Sun Jul 28 20:54:44 2002) WWW-POST
比如我要做的工作是, 当人们选了state以后, 后面county选项的下拉选单就自动列出
该州的所有county供选择.
一般这种cascading的选择, 都是用function, function里面用array列出所有选项. 可我
的项目显然不能够让所有的州的county都列在function里, 而是应该储存在数据库里. 应
该把选择的州作为参数, 送给function, 让function去query database, 在把county
array返回.
可是我们可以在vbscript或javascript里建立数据库连接, query database 吗?
谁能指点一二, 谢谢了. |
|
p*p
发帖数: 80 | 27 Could someone help me with the following query? Say there is a table with 2
columns, ProductID and ProductType
ProductID ProductType
1 C
2 B
3 A
4 B
5 A
6 C
7 A
8 B
how to write a query to return 2 products (order by ProductID) from each
producttype? In this case, return:
3 A
5 A
2 B
4 B
1 C
6 C
Use Transact-SQL, one query, no cursor is allowed.
Please help!!!! |
|
c**t
发帖数: 2744 | 28 A very complex query has remote query in it.
Will it be faster to create a view for the remote query? |
|
w******i
发帖数: 1476 | 29 I add "NAME_PREFERRED" in "hr_contact_add" table and the error message shows
up. I don't know whether it is exactly the problem. But yesterday this query
(Query 3) didn't give me any problem and I even used its results for another
two higher-level queries.
Yup, they are both unique since they are primary keys in their individual
tables.
Correct me if I were wrong here. thanks a lot!
((([dbo_HRPEOPLE_ADDRESSES11].[ADDRESS_TYPE])=[dbo_HRPEOPLE11].[PRIMARY_MAIL_T
([dbo_HRPEOPLE_PHONES11].[PHONE_TY |
|
f********g
发帖数: 845 | 30 我们的数据库在另外一个州，从前我都是
link to the tables from Access, 但是query就很慢
今天发现还有pass-through query这个选择。请问
应该怎样用pass-through query to make tables, such
that the execution is done on the database engine in the
other state, while the result table is created in the
local Access interface
多谢多谢 |
|
c********e
发帖数: 2 | 31 I am doing some sql queries which need to join several tables in a
relatively large MySql database(version 4.**).
I've optimized the WHERE clause but the speed of the query is very slow...
Is it going to be faster if I write some API instead of doing direct query?
Please give me some suggestions!Thanks! |
|
t**********s
发帖数: 930 | 32 I am reading FUNDAMENTALS OF DATABASE SYSTEMS where it says "In general, a
query written with nested SELECT...FROM...WHERE... blocks and using = or IN
comparison operators can always be expressed as a single block query."
I believe this is true.
Now I wonder whether similar structure with 'NOT IN' comparison operator
can be expressed as a single block query.
Can any body give me an example? |
|
f*****e
发帖数: 5177 | 33 I run SQL query estimated execution plan again one query.
The plan showed that the cost of "delete" and "insert" is 900%.
What does that mean?
PS: Which one of the following queries is better?
Query1:
if exist (select * from table1 where ...)
begin
update table1 set ...
end
else
begin
insert into table1 ...
end
Query2:
if exist (select * from table1 where ...)
begin
delete from table1 where ...
end
insert into table1 ...
Query3:
delete from table1 where ...
insert into table1 ... |
|
r****r
发帖数: 1693 | 34 I have a query to run against a db with millions and millions of entries.
I'd like to test the query before running it against the entire db.
Is there a way to run the query against only the first 1000 entries?
5000 entries? X entries? Not 'LIMIT' 'TOP', they are for limitation only
on the result.
Thank you very much!!! |
|
c***c
发帖数: 6234 | 35 我有两个tables，incidents 和 ConfigurationItems
每个incident都必须有Configuration Item。
但一些Apps把错误的Configuration Item名字放到incident里了。大概400W个incident
，15000个Configuration Items。
我怎么能用最有效的query把所有有无效的Configuration Item incident query 出来
呢？
select incident_id from incidents
where ci_name not in (select ci_name from configurationitems)
怎么return 0 row
有没有更有效的query呢？
谢谢 |
|
g***l
发帖数: 18555 | 36 不能用，INNER QUERY出来的是个集合，每个FIELD3---MAX FIELD2，OUTER QUERY没法
直接QUERY这个集合，只能是JOIN起来 |
|
d*******n
发帖数: 109 | 37 this is a single table query,
table looks like this:
column1 column2 column3 column4
1 0 1 0
0 1 1 1
1 0 0 0
1 1 1 1
...
four columns, each can be 1 or 0,
write one SQL query to get output looks like
TotalRow Count1 Count23 Count4
total row is the total row of table
count1 is the count of all row which column1 = 1 and the rest 3 columns are
0
count23 is the count of all row which... 阅读全帖 |
|
l******9
发帖数: 579 | 38 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: change year format in Access by SQL query
发信站: BBS 未名空间站 (Mon Oct 13 12:50:53 2014, 美东)
I am working on Access 2012 on win 7. In a table, I need to change a year
date format from '1-Jan-06' to 2006 and from '1-Jan-90' to 1990. I only need
year.
This is my query
SELECT *,
CASE
WHEN CAST(right(year_date,2) , INT) <= 12
THEN 2000 + CAST(right(year_date,2) , INT)
ELSE 1900 + CAST(right(year_date,2) , INT)
END
FROM my_table;
I ... 阅读全帖 |
|
l******9
发帖数: 579 | 39 【 以下文字转载自 JobHunting 讨论区 】
发信人: light009 (light009), 信区: JobHunting
标 题: error of sql query in MS Access database
发信站: BBS 未名空间站 (Wed Oct 15 17:38:15 2014, 美东)
I need to do a sql query in MS Access 2012.
But I got error in MS Access:
SELECT *
FROM
(
SELECT *
FROM table1
where not exists
(
SELECT *
FROM table2
where table2.id = table1.id
) as t
) as t1, table3
where table3.id = t1.id
Syntax error: (missing operator) in query expression 'not exists ( ... ) as
t'
A... 阅读全帖 |
|
l******9
发帖数: 579 | 40 【 以下文字转载自 JobHunting 讨论区 】
发信人: light009 (light009), 信区: JobHunting
标 题: Error of SQL query on IBM netezza SQL database from Aginity workbench
发信站: BBS 未名空间站 (Fri Dec 5 16:46:56 2014, 美东)
I need to so a sql query on IBM netezza sql database from Aginity workbench
on win7.
My query:
SELECT *
from table1 AS c ,
table2 AS b
where CAST(c.id as int) = b.id
in table1, id is character varying(20) and in table2, id is int.
Table1:
id value1 value2
'985' 'casdqwdc' '654.3184' // t... 阅读全帖 |
|
g*********g
发帖数: 171 | 41 Because the second query has a much smaller union. macan may have thought
about it already.
My result showed that the 2nd query completed in 9 sec vs 11 sec for the 1st
query.
Here is my test in SQLITE:
drop table a;
drop table b;
create table a (id text);
create table b (id text);
delete from A;
delete from B;
insert into A WITH RECURSIVE cnt(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM
cnt WHERE x<10000000) SELECT x FROM cnt;
insert into B WITH RECURSIVE cnt(x) AS (VALUES(1) UNION ALL SELECT x... 阅读全帖 |
|
m******u
发帖数: 12400 | 42 date在SQL Server里是一种数据类型，所以是保留字，不能用于变量名（这里也即列名
）要用作列名要加个中括号。你的query在sql server中不work。
发信人: mdrosophila (ranger), 信区: Database
标 题: Re: 这个query对么？
发信站: BBS 未名空间站 (Tue Jun 23 22:15:03 2015, 美东)
我的SQL没有正式学过，就是工作中有很多的server side 的SQL
所以我不是dba,就是一个用到简单SQL 的吗农
我没有看懂你说的date要加括号是啥意思
这个query在你的系统，我猜是microsoft sql server中可以run不？ |
|
l******9
发帖数: 579 | 43 【 以下文字转载自 Quant 讨论区 】
发信人: light009 (light009), 信区: Quant
标 题: change year format in Access by SQL query
发信站: BBS 未名空间站 (Mon Oct 13 12:50:53 2014, 美东)
I am working on Access 2012 on win 7. In a table, I need to change a year
date format from '1-Jan-06' to 2006 and from '1-Jan-90' to 1990. I only need
year.
This is my query
SELECT *,
CASE
WHEN CAST(right(year_date,2) , INT) <= 12
THEN 2000 + CAST(right(year_date,2) , INT)
ELSE 1900 + CAST(right(year_date,2) , INT)
END
FROM my_table;
I ... 阅读全帖 |
|
l******9
发帖数: 579 | 44 【 以下文字转载自 JobHunting 讨论区 】
发信人: light009 (light009), 信区: JobHunting
标 题: error of sql query in MS Access database
发信站: BBS 未名空间站 (Wed Oct 15 17:38:15 2014, 美东)
I need to do a sql query in MS Access 2012.
But I got error in MS Access:
SELECT *
FROM
(
SELECT *
FROM table1
where not exists
(
SELECT *
FROM table2
where table2.id = table1.id
) as t
) as t1, table3
where table3.id = t1.id
Syntax error: (missing operator) in query expression 'not exists ( ... ) as
t'
A... 阅读全帖 |
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l******9
发帖数: 579 | 45 【 以下文字转载自 JobHunting 讨论区 】
发信人: light009 (light009), 信区: JobHunting
标 题: Error of SQL query on IBM netezza SQL database from Aginity workbench
发信站: BBS 未名空间站 (Fri Dec 5 16:46:56 2014, 美东)
I need to so a sql query on IBM netezza sql database from Aginity workbench
on win7.
My query:
SELECT *
from table1 AS c ,
table2 AS b
where CAST(c.id as int) = b.id
in table1, id is character varying(20) and in table2, id is int.
Table1:
id value1 value2
'985' 'casdqwdc' '654.3184' // t... 阅读全帖 |
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t***q
发帖数: 418 | 46 如题，要建一个 web service， 有 query string 的功能。主要是，有一个 影视作品
的title 进来，用 web service 里的 一些function, 和已有的一个 flat file, 那个
flat file里，有许多影视作品的 title , 及其他一些信息， 用这个 flat file, 和
已输入的 title, 算出与之最相似的影视作品的title, 然后 call 相关 url 后， 能
有一个 hash table 输出， 其中有最相近的 title ， 和 相似率， 一个类似
confidence level 的东西。
例子如下：
http://www.dreamsyssoft.com/python-scripting-tutorial/create-si
现在就是不知道如何把query string ， 还有算 相似度的function 加进去。其实自己
也不知道这个例子到底有没有用，对这个问题。谁能说说？还有就是哪位能给个 web
service 用 query string的标准的例子，链接之类的。多谢！ |
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d****n
发帖数: 1637 | 47 你的array 不用 lock么？
不同时间的query 返回，都要 arr.push(result), 这不是明显的racing问题么？
还有
var results = [];
var numWantedResults = 10 ;
for ( i=0;i
ret = connectToDb(.., function (err, rows){
results.push(rows);
//你能保证length, push都同步么？最后一个回来的query 都认为自己是倒数最
后一个，
//永远也不能返回了。
//double callback也有可能，在每个query都认为自己是最后一个的情况，
//你的系统就 咣，咣，咣 了
if( results.length == numWantedResults ){
return results; //
}
})
}
如果加lock,sycn那和async, promise 有什么区别？ |
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d*******n
发帖数: 524 | 48 【 以下文字转载自 Database 讨论区 】
发信人: dArtagnan (达达尼昂), 信区: Database
标 题: How to write this query in Oracle?
发信站: BBS 未名空间站 (Tue Dec 8 10:42:40 2009, 美东)
We have a table (T_1) with e.g. 4 columns
T_1:
x y x z
1 2 3 4
3 6 1 -1
6 3 2 0
5 3 2 -10
I need a query to find out in each row which column has the max absolute value.
That is, I need to get the following table as output:
max_col
z
y
x
z
How to write this query in Oracle?
Thanks |
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d*******y
发帖数: 1154 | 49 这俩query不一样
第一个query是把所有选过science的学生记录都调出来。
比如一个学生选了science, math, art，那么他的三个记录都会被调出来。
第二个query不能调出math和art |
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