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Persistence unit as RESOURCE_LOCAL or JTA?
...
You must use the
EntityTransaction API to begin/commit around
every call to your EntityManger Calling
entityManagerFactory.createEntityManager() twice results in
two separate EntityManager instances and therefor
two separate PersistenceContexts/Caches. It
is almost never a good idea t...
Creating Threads in python
...rgument in the Thread constructor to directly pass in a function that gets called instead of run.
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Django using get_user_model vs settings.AUTH_USER_MODEL
.../ManyToMany-relation.
From the changelog:
get_user_model() can now be called at import time, even in modules that define models.
so... is there still a reason to use settings.AUTH_USER_MODEL? Well, the docs still recommend the settings.AUTH_USER_MODEL (which is a string) for defining relation...
How to check if a Constraint exists in Sql server?
...E, PRIMARY KEY, FOREIGN KEY, and/or DEFAULT
SELECT
OBJECT_NAME(OBJECT_ID) AS NameofConstraint
,SCHEMA_NAME(schema_id) AS SchemaName
,OBJECT_NAME(parent_object_id) AS TableName
,type_desc AS ConstraintType
FROM sys.objects
WHERE type_desc LIKE '%CONSTRAINT'
...
What is the recommended way to use Vim folding for Python code
...ode.
#Toggle fold methods \fo
let g:FoldMethod = 0
map <leader>fo :call ToggleFold()<cr>
fun! ToggleFold()
if g:FoldMethod == 0
exe 'set foldmethod=indent'
let g:FoldMethod = 1
else
exe 'set foldmethod=marker'
let g:FoldMethod = 0
endif
endfu...
Difference Between ViewData and TempData?
...se it all the time, but in ASP.NET Preview 5 they introduced something new called TempData.
6 Answers
...
Hibernate: “Field 'id' doesn't have a default value”
...e AUTO_INCREMENT. See the example below.
CREATE TABLE `supplier`
(
`ID` int(11) NOT NULL **AUTO_INCREMENT**,
`FIRSTNAME` varchar(60) NOT NULL,
`SECONDNAME` varchar(100) NOT NULL,
`PROPERTYNUM` varchar(50) DEFAULT NULL,
`STREETNAME` varchar(50) DEFAULT NULL,
`CITY` varchar(...
Modifying location.hash without page scrolling
...
Step 1: You need to defuse the node ID, until the hash has been set. This is done by removing the ID off the node while the hash is being set, and then adding it back on.
hash = hash.replace( /^#/, '' );
var node = $( '#' + hash );
if ( node.length ) {
node....
IN clause and placeholders
I'm attempting to do the following SQL query within Android:
9 Answers
9
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Add new column with foreign key constraint in one command
...d by commas. For example...
Informix syntax:
ALTER TABLE one
ADD two_id INTEGER,
ADD CONSTRAINT FOREIGN KEY(two_id) REFERENCES two(id);
The syntax for IBM DB2 LUW is similar, repeating the keyword ADD but (if I read the diagram correctly) not requiring a comma to separate the added items...