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Removing a model in rails (reverse of “rails g model Title…”)
...oy' on that model, it will delete the migration file, but not the database table. So before run
bundle exec rake db:rollback
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Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he solution is replace primitive type with primitive wrapper class in your tableName.java file.
Such as:
@Column(nullable=true, name="client_os_id")
private Integer client_os_id;
public int getClient_os_id() {
return client_os_id;
}
public void setClient_os_id(int clientOsId) {
client_os_...
Difference between partition key, composite key and clustering key in Cassandra?
...neral concept to indicate one or more columns used to retrieve data from a Table.
The primary key may be SIMPLE and even declared inline:
create table stackoverflow_simple (
key text PRIMARY KEY,
data text
);
That means that it is made by a single column.
But the primary ke...
Laravel Eloquent: How to get only certain columns from joined tables
I have got 2 joined tables in Eloquent namely themes and users.
15 Answers
15
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How do I create an Excel (.XLS and .XLSX) file in C# without installing Microsoft Office?
...asy to use. Plus it has a DataSetHelper that lets you use DataSets and DataTables to easily work with Excel data.
ExcelLibrary seems to still only work for the older Excel format (.xls files), but may be adding support in the future for newer 2007/2010 formats.
You can also use EPPlus, which work...
How to check Oracle database for long running queries
... object_name
/
This is a good one for finding long operations (e.g. full table scans). If it is because of lots of short operations, nothing will show up.
COLUMN percent FORMAT 999.99
SELECT sid, to_char(start_time,'hh24:mi:ss') stime,
message,( sofar/totalwork)* 100 percent
FROM v$session_l...
Why is a round-trip conversion via a string not safe for a double?
...x-1];
// the exponents are shared between the inverted and regular table
exp += (scale < 0) ? (-multexp + 1) : multexp;
unsigned long long multval = rgval64Power10[index + ((scale < 0) ? 15 : 0) - 1];
val = Mul64Lossy(val, multval, &exp);
}
index =...
Best dynamic JavaScript/JQuery Grid [closed]
...
Free:
Gijgo Grid
Backgrid.js
Flexigrid
jqGridView
Ingrid
SlickGrid
DataTables
Shield UI Lite Grid
Paid:
Fancy Grid
jQuery Grid
jqxGrid
Shield UI Grid
The best entries in my opinion are Flexigrid and jQuery Grid.
sh...
Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alternatively delete the entity and then add it) before you stop getting the error.
...
cartesian product in pandas
... 6
See here for the documentation: http://pandas.pydata.org/pandas-docs/stable/merging.html#brief-primer-on-merge-methods-relational-algebra
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