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CASCADE DELETE just once
...esql database on which I want to do a few cascading deletes. However, the tables aren't set up with the ON DELETE CASCADE rule. Is there any way I can perform a delete and tell Postgresql to cascade it just this once? Something equivalent to
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Extending the User model with custom fields in Django
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Since Django 1.5 you may easily extend the user model and keep a single table on the database.
from django.contrib.auth.models import AbstractUser
from django.db import models
from django.utils.translation import ugettext_lazy as _
class UserProfile(AbstractUser):
age = models.PositiveInteg...
Why would you use an ivar?
... in the implementations of an accessor, a convenience constructor, copy, mutableCopy, and archiving/serialization implementations.
It's also more frequent as one moves from the everything has a public readwrite accessor mindset to one which hides its implementation details/data well. Sometimes you n...
Which is more efficient, a for-each loop, or an iterator?
...n invokeInterface virtual call (go through all the classes, then do method table lookup before the jump).
the implementation of the iterator has to do at least 2 fields lookup in order to make hasNext() call figure the value: #1 get current count and #2 get total count
inside the body loop, there is...
How to export query result to csv in Oracle SQL Developer?
...take an export to your local system from sql developer.
Path : C:\Source_Table_Extract\des_loan_due_dtls_src_boaf.csv
SPOOL "Path where you want to save the file"
SELECT /*csv*/ * FROM TABLE_NAME;
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Search text in fields in every table of a MySQL database
I want to search in all fields from all tables of a MySQL database a given string, possibly using syntax as:
24 Answers
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How do you truncate all tables in a database using TSQL?
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For SQL 2005,
EXEC sp_MSForEachTable 'TRUNCATE TABLE ?'
Couple more links for 2000 and 2005/2008..
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Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'?,./
...rs can't be represented more simply with a range: !"^_`[].
Use an ACSII table to find ranges for character classes.
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How to rename a single column in a data.frame?
...estion, but it is worth noting that you can now use setnames from the data.table package.
library(data.table)
setnames(DF, "oldName", "newName")
# or since the data.frame in question is just one column:
setnames(DF, "newName")
# And for reference's sake, in general (more than once column)
nms ...
Find a value anywhere in a database
Given a #, how do I discover in what table and column it could be found within?
18 Answers
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