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How to get distinct values for non-key column fields in Laravel?
...lder you can do it this way:
$users = DB::table('users')
->select('id','name', 'email')
->groupBy('name')
->get();
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...
Oracle “(+)” Operator
...dize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recommends not using it:
Oracle re...
CROSS JOIN vs INNER JOIN in SQL
...ame situation.
These 2 examples will return the same result:
Cross join
select * from table1 cross join table2 where table1.id = table2.fk_id
Inner join
select * from table1 join table2 on table1.id = table2.fk_id
Use the last method
...
Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
Similarity String Comparison in Java
...ns Text's implementation of Levenshtein distance:
apply(CharSequence left, CharSequence rightt)
Implement it in your own. Below you'll find an example implementation.
Working example:
See online demo here.
public class StringSimilarity {
/**
* Calculates the similarity...
Change limit for “Mysql Row size too large”
...rows of your
tables plus the length of other variable length fields (VARCHAR, VARBINARY, and TEXT type fields).
In my situation the offending blob table was around 16MB. Thus, the way I solved it was by adding a line to my.cnf that ensured I had at least 10x that amount and then some:
innodb_l...
An explicit value for the identity column in table can only be specified when a column list is used
...tead of
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table
SELECT *
FROM source_table;
SET IDENTITY_INSERT archive_table OFF;
you need to write
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table (field1, field2, ...)
SELECT field1, field2, ...
FROM source_table;...
Effective method to hide email from spam bots
...'@'), indexOf('mailto:'), etc. The parsing thread would receive only +-200 chars around the match which would allow so complex parsing that it would 'appear' to be infinite in terms of parsing power.
– Jani Hyytiäinen
Feb 28 '15 at 8:33
...
Select 50 items from list at random to write to file
... leaving the original population unchanged. The resulting list is
in selection order so that all sub-slices will also be valid random
samples. This allows raffle winners (the sample) to be partitioned
into grand prize and second place winners (the subslices).
Members of the popul...
Google Sheets API Setup · App Inventor 2 中文网
...ou have not created a project
before, you can create your first project by selecting [CREATE PROJECT].
If you are using an existing Developer Account and already have a Project, you
will be on a Project’s Dashboard. To create a new Project, click on the drop
down menu at the top of the webpage....