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How to debug Lock wait timeout exceeded on MySQL?
...the query was attempting to change at least one row in one or more InnoDB tables.
Since you know the query, all the tables being accessed are candidates for being the culprit.
From there, you should be able to run SHOW ENGINE INNODB STATUS\G
You should be able to see the affected table(s)
You get a...
django syncdb and an updated model
...ngo currently does not do this automatically. Your options are:
Drop the table from the database, then recreate it in new form using syncdb.
Print out SQL for the database using python manage.py sql (appname), find the added line for the field and add it manually using alter table SQL command. (Th...
Alternate table row color using CSS?
I am using a table with alternate row color with this.
9 Answers
9
...
SQL “select where not in subquery” returns no results
... query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM table1 t1
WHERE t1.common_id = ...
Does Foreign Key improve query performance?
Suppose I have 2 tables, Products and ProductCategories. Both tables have relationship on CategoryId. And this is the query.
...
How do I split a string so I can access item x?
...-in function STRING_SPLIT that will split a string and return a one-column table result which you can use in a SELECT statement or elsewhere.
– qJake
Apr 3 '17 at 20:24
...
How to select from subquery using Laravel Query Builder?
...Abc::where(..)->groupBy(..); // Eloquent Builder instance
$count = DB::table( DB::raw("({$sub->toSql()}) as sub") )
->mergeBindings($sub->getQuery()) // you need to get underlying Query Builder
->count();
Mind that you need to merge bindings in correct order. If you have ot...
How to prevent line-break in a column of a table cell (not a single cell)?
How can I prevent automatic line breaks in a column of table (not a single cell)?
9 Answers
...
MySQL Error 1093 - Can't specify target table for update in FROM clause
I have a table story_category in my database with corrupt entries. The next query returns the corrupt entries:
16 Answers...
Select statement to find duplicates on certain fields
...ltiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There should be a criterion for deciding how you defi...