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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
..., something like this:
CONSTRAINT region_ibfk_1 FOREIGN
KEY (country_id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACTION
Now simply issue an:
alter table region drop foreign key
region_ibfk_1;
And finally an:
alter table region drop column
country_id;
And ...
mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...
Maven: Non-resolvable parent POM
... the same directory (same project). But this doesn't solve this error. Any idea how to fix it?
– Praneeth Peiris
Apr 5 '19 at 9:26
...
How to remove padding around buttons in Android?
In my Android app, I have this layout:
17 Answers
17
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What's the difference between TRUNCATE and DELETE in SQL
...to be faster than a DELETE.
Various system-specific issues have to be considered, as detailed below.
Statement type
Delete is DML, Truncate is DDL (What is DDL and DML?)
Commit and Rollback
Variable by vendor
SQL*Server
Truncate can be rolled back.
PostgreSQL
Truncate can be rolled back...
How to explore web-based Google Play in another country?
if I go to play.google.com, it automatically recognizes my country and allow me to browse the apps for that country. I can change the language through the dropdown in the footer, or I can add &hl=code in the querystring...but that only changes the language...not the store content (the app lists and ...
how to read System environment variable in Spring applicationContext
...ng 3.0 adds Spring Expression Language.
You can use
<util:properties id="dbProperties"
location="classpath:config_#{systemProperties['env']}/db.properties" />
Combined with java ... -Denv=QA should solve your problem.
Note also a comment by @yiling:
In order to access system env...
Check if an element is a child of a parent
...ive it the selector, as in target.parent('div#hello').
Example: http://jsfiddle.net/6BX9n/
function fun(evt) {
var target = $(evt.target);
if (target.parent('div#hello').length) {
alert('Your clicked element is having div#hello as parent');
}
}
Or if you want to check to ...
COUNT DISTINCT with CONDITIONS
...elect
count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex, is actually the same as the first one, except that you use case...when cla...
How to rename a single column in a data.frame?
... answered May 10 '13 at 20:33
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