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I can not find my.cnf on my windows computer [duplicate]
...ces.msc, Enter
You should find an entry like 'MySQL56', right click on it, select properties
You should see something like "D:/Program Files/MySQL/MySQL Server 5.6/bin\mysqld" --defaults-file="D:\ProgramData\MySQL\MySQL Server 5.6\my.ini" MySQL56
Full answer here:
https://stackoverflow.com/a/20136...
Why can't a text column have a default value in MySQL?
... I try to recreate the table locally with the obvious default (based on a select of unique values for that column) and end up receiving the oh-so-useful BLOB/TEXT column can't have a default value.
Again, not maintaining basic compatability across platforms is unacceptable and is a bug.
How to ...
PHP MySQL Google Chart JSON - Complete Example
... else
{
//echo ("Connect Successfully");
}
$query = "SELECT Date_time, Tempout FROM alarm_value"; // select column
$aresult = $con->query($query);
?>
<!DOCTYPE html>
<html>
<head>
<title>Massive Electronics</title>
<script ty...
Counting null and non-null values in a single query
...le and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
...
Is it possible to specify condition in Count()?
...an use the fact that the count aggregate only counts the non-null values:
select count(case Position when 'Manager' then 1 else null end)
from ...
You can also use the sum aggregate in a similar way:
select sum(case Position when 'Manager' then 1 else 0 end)
from ...
...
MySQL root password change
I have been trying to reset my MySQL root password. I have run the mysqld_safe --skip-grant-tables, updated the root password, and checked the user table to make sure it is there. Once restarting the mysql daemon I tried logging in with the new root password that I just set and still get Access de...
How to randomly select rows in SQL?
...
SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT...
Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
...
Return a value if no rows are found in Microsoft tSQL
...
SELECT CASE WHEN COUNT(1) > 0 THEN 1 ELSE 0 END AS [Value]
FROM Sites S
WHERE S.Id = @SiteId and S.Status = 1 AND
(S.WebUserId = @WebUserId OR S.AllowUploads = 1)
...
What is the PostgreSQL equivalent for ISNULL()
...
SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
share...