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Var auditAgencyRecords = (from ag in db.Agencies join ara in db.AuditRuleAccounts on ag.Agency_Id equals ara.AgencyID join arr in db.AuditRuleResults on ara.AuditRuleAccountID equals arr.AuditRuleAccountID join are in db.AuditRuleEnterprises on arr.AuditRuleEnterpriseID...
Started by KingNestor on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at stackoverflow):
AuditAgencyRecords = ( from ag in db.Agencies group join ara in db.AuditRuleAccounts on ag.Agency_Id equals ara.AgencyID into AgAra = group from w in AgAra.DefaultIfEmpty() group join arr in db.AuditRuleResults in AraArr.DefaultIfEmpty(....
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Hello, I develop against Oracle databases. When I need to manually write (not use an ORM like hibernate), I put join statements in the where clause sections.
for example (this is simplistic just to illustrate the style):
Select * from customers c, invoices...
Started by Jay on
, 11 posts
by 11 people.
Answer Snippets (Read the full thread at stackoverflow):
The old style join is flat out wrong in some cases (outer joins, this syntax is more portable....
It supports LEFT, RIGHT, and FULL OUTER JOINs brought up eating it love it.
The filtering WHERE conditions from the JOIN conditions.
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Are there any performance drawbacks in SQL to joining a table on a char (or varchar) value, as opposed to say joining on an integer value?
Started by Aaron F. on
, 6 posts
by 6 people.
Answer Snippets (Read the full thread at stackoverflow):
An integer....
No, as long as the datatypes are the same between the tables that you join of the join column.
What can make a difference is:
- If datatypes in your join-condition than in the other column.
No there is not (in Oracle).
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I've got a table of temperature samples over time from several sources and I want to find the minimum, maximum, and average temperatures across all sources at set time intervals. At first glance this is easily done like so:
SELECT MIN(temp), MAX(temp)...
Started by pr1001 on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at stackoverflow):
Solution that will work though:
-- Full join across the sample set and anything missing from the sample join ( -- Pull all the time/source combinations that we are missing from the sample set, along join (select distinct source from....
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I am trying to determine the performance of a piece of generated SQL that runs in SQL Server 2005.
It uses CROSS JOINS, but the conditionals tying the cross joined tables are in the where statement.
I previously thought that all cross joins that have ...
Started by jetimms on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at stackoverflow):
Select companies.id, contacts.id from companies cross join contacts where contacts.companyid = companies.id select companies.id, contacts.id from....
And 'on' clauses during join operations, and i imagine the same is for cross joins.
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I am learning SQL and am trying to learn JOINs this week.
I have gotten to the level where I can do three table joins, similar to a lot of examples I've seen. I'm still trying to figure out the tiny details of how things work. All the examples I've seen...
Started by MedicineMan on
, 9 posts
by 9 people.
Answer Snippets (Read the full thread at stackoverflow):
The same....
It just depends on the data you are querying and what you are trying to follow .
I also use FULL OUTER JOIN s and CROSS JOIN an outer join in them.
OUTER) JOIN s instead of inter-mixing LEFT and RIGHT JOINs.
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Is it true that no matter which type of join you use, if your WHERE clause checks one table's pk = other table's fk, it becomes same as an inner join as far as the result set is conncerned? In other words, if your sql query has some stuff like:
"Select...
Answer Snippets (Read the full thread at stackoverflow):
Edit: I should also noteYes, that is a roundabout....
So, in short: use inner joins if you really want an inner join.
Outer joins, as it will do the join and then filter (depending on the filters, of course, and the optimizer).
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I use INNER JOIN and LEFT OUTER JOINs all the time. However, I never seem to need RIGHT OUTER JOINs, ever.
I've seen plenty of nasty auto-generated SQL that uses right joins, but to me, that code is impossible to get my head around. I always need to rewrite...
Started by KM on
, 11 posts
by 11 people.
Answer Snippets (Read the full thread at stackoverflow):
Also I naturally tend to order the data, so that left joins work for gettingNo, I don't for....
The only time I use a Right outer join is when I am working and use a left join.
Interestingly enough, I rarely used right joins.
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Are there any performance issues if an sql query contains lot of joins?
Started by jayaprakashbr on
, 6 posts
by 6 people.
Answer Snippets (Read the full thread at stackoverflow):
Read more in this article
Performance....
If you join three tables and both the joins require full file reads, you could be in a world of hurtOne of the best ways to boost JOIN performance is to limit how many rows need to be JOINed.
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I am wondering how to differentiate all these different joins ...
Answer Snippets (Read the full thread at stackoverflow):
Inner join....
Every row from both tables joins.
Full outer join : A combination of left and right outer joins.
An output row is produced reversed.
Joins
There are only 4 kinds:
Inner join : The most common type.
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