|If Inner Join can be thought of as Cross Join but filtering out the records satisfying the condition, then Left Outer Join is the above, plus 1 record|
| by JEDI in Programming Languages|
If an Inner Join can be thought of as a cross join and then getting the
records that satisfy the condition, then a LEFT OUTER JOIN can be thought
of as that, plus ONE record on the left table that doesn't satisfy the
In other words, it is not a cross join that "goes
easy" on the left records (even when the condition is not satisfied),
because then the left record can appe
|can the natural-join be seen as a subset of the equi-join and theta-join?|
| by Alatar in Databases|
I have a question regarding relational algebra and how the theta-join,
equi-join, and natural-join can be classified in relation to each
In a comment on stackoverflow.com sqlvogel quotes E.F.
Codd, the computer scientist who invented the relational model for database
management, "[the] Natural[-join] is a subset of Equi[-join] which is a
subset of Theta[-join]."
|Inner join on a left join makes the left join behave as a inner join|
| by l1feh4ck3r in Databases|
I have a two lookup tables that I want to inner join on each other,
however I only want to left join on my data table.
LEFT JOIN [ENTRY]
on [ENTRY].ENTRY_CODE =
and [ENTRY].ENTRY_RECD = 'A'
on [ENTRY_TYPES].ENTRY_TYPES_FileRecordID =
|LEFT JOIN or REGULAR JOIN, and how to compare MySql table to an array? Need performance!|
| by MikeT in Programming Languages|
I have six tables: t1, t2, t3, t4, t5, t6. And I also have one main
table: main_table. TOTAL 7 TABLES!
Now, I am using SOLR for the
searching of classifieds, and the results from solr are put into an array.
The array results are ID:nrs which I use to match agains the same ID:s in
The first column of ALL tables in MySql is called
If the u
|CRM LINQ Composite join “The method 'Join' is not supported” error|
| by JSebok in Programming Languages|
Im getting a "The method 'Join' is not supported" error... Funny thing
is that i simply converted the 1st LINQ into the 2nd version and it doesnt
What i wanted to have was LINQ version #3, but it also
var query_join9 = from
s in orgSvcContext.CreateQuery(ServiceAppointment.EntityLogicalName)
join b in orgSvcContext.Cr
|mysql: How to INNER JOIN a table but limit join to 1 result with the highest vote or count?|
| by Mansur in Databases|
I have 2 tables. One is items and another is votes for those
Items table has: |item_id|name|post_date
table has: |votes_id|item_id|answer|total_yes|total_no
What I want to do is show all items based on post_date and show the
answer in the votes table with the HIGHEST total_yes. So I want to show
only a SINGLE answer from the votes table with
|Create a VIEW where a record in t1 is not present in t2 ? Confirmation on Union/Left Join/Inner Join?|
| by joshboles in Databases|
I am trying to make a view of records in t1 where the source id from t1
is not in t2.
Like... "what records are not present in the
Do I need to include t2 in the FROM clause?
SELECT t1.fee_source_id, t1.company_name,
WHERE t1.fee_source_id NOT IN (
FROM t1 INNER
|Difference between Nested loop join and hash join in SQL Server 2008|
| by qba73 in Databases|
What is the primary difference between a nested loop join and a hash
join? I dont have any idea about this and all I know is that they appear on
the execution plan of a query. Can anyone shed some light on this?
|Oracle outer join not giving expected results (behaving like inner join)|
| by negonicrac in Databases|
where table_a.id = table_b.id(+)
and table_b.name =
returns me no records. table_b has no
records with name='BENEFICIARY'. But the outer join should return all
records from table_a regardless . No?
The below query returns records
from table_a as expected:
|Django ForeignKey with null=True, inner join, and left outer join|
| by cbridi in Web Design|
Let's say I have two Django models Person and Company as follows: -
first_name = models.CharField()
company = models.ForeignKey(Company, null=True, blank=True)
A Person may or may not belong to a