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Storing JSON in database vs. having a new column for each key
I am implementing the following model for storing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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Django dump data for a single model?
...Django dumpdata management command allows you to dump data from individual tables:
./manage.py dumpdata myapp1 myapp2.my_model
You can also separate multiple apps and models on the command line. Here's the canonical definition:
django-admin dumpdata [app_label[.ModelName] [app_label[.ModelName] ...
Best way to test SQL queries [closed]
...endently tested to find errors, and the tests are simple.
Here's the base table in the example:
create table month_value(
eid int not null, month int, year int, value int );
This table is flawed, because it uses two columns, month and year, to represent one datum, an absolute month. Here's...
Why do people hate SQL cursors so much? [closed]
...I. Cursors are how parts of the RDBMS work under the hood. Often CREATE TABLE and INSERT have SELECT statements, and the implementation is the obvious internal cursor implementation.
Using higher-level "set-based operators" bundles the cursor results into a single result set, meaning less API b...
Differences between MySQL and SQL Server [closed]
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I can't believe that no one mentioned that MySQL doesn't support Common Table Expressions (CTE) / "with" statements. It's a pretty annoying difference.
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Why can't C# interfaces contain fields?
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The virtual keyword is implemented in .NET with methods and a so-called v-table, an array of method pointers. The override keyword fills the v-table slot with a different method pointer, overwriting the one produced by the base class. Properties, events and indexers are implemented as methods und...
Query to list all stored procedures
...m my understanding the "preferred" method is to use the information_schema tables:
select *
from information_schema.routines
where routine_type = 'PROCEDURE'
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Datatable vs Dataset
I currently use a DataTable to get results from a database which I can use in my code.
7 Answers
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Accessing an SQLite Database in Swift
...en it is no longer required.
Use sqlite3_exec to perform SQL (e.g. create table).
if sqlite3_exec(db, "create table if not exists test (id integer primary key autoincrement, name text)", nil, nil, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
print("error creating t...
how to show alternate image if source image is not found? (onerror working in IE but not in mozilla)
I need to show an alternate image in cell of table if source image is not found.
Currently below code is used to do so.
3 A...