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Simulating group_concat MySQL function in Microsoft SQL Server 2005?
...sy way to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern....
MySQL - Using COUNT(*) in the WHERE clause
...
try this;
select gid
from `gd`
group by gid
having count(*) > 10
order by lastupdated desc
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How to Get True Size of MySQL Database?
... would like to know how much space does my MySQL database use, in order to select a web host.
I found the command SHOW TABLE STATUS LIKE 'table_name' so when I do the query, I get something like this:
...
What's the difference between array_merge and array + array?
...
The difference is:
The + operator takes the union of the two arrays, whereas the array_merge function takes the union BUT the duplicate keys are overwritten.
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Convert MySql DateTime stamp into JavaScript's Date format
...d.
A MySQL DATETIME column can be converted to a unix timestamp through:
SELECT unix_timestamp(my_datetime_column) as stamp ...
We can make a new JavaScript Date object by using the constructor that requires milliseconds since the epoch. The unix_timestamp function returns seconds since the epoc...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
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The second approach should be used selectively, i. e. never be applied to SELECT queries, as set names utf8mb4; select ... from ... will never produce a ResultSet and instead result in a ResultSet is from UPDATE. No Data. error.
– Bass
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MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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How can I return pivot table output in MySQL?
...OUP BY.
The basic SQL providing this pivot can look something like this:
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... up the firstname field as shown.
http://localhost:8983/solr/collection1/select?q=firstname:john^2&lastname:john
As you can see, firstname field is boosted up with a score of 2.
More on SolrRelevancy
searching and indexing speed
The speed is unbelievably fast and no compromise o...
What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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