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Avoiding instanceof in Java
...o make the logic of "handle" part of each 'switching' class - i.e. Integer etc. in this case. Clearly this is not practical. Sometimes it isn't even logically the right place to put the code. He recommends the 'instanceof' approach as being the lesser of several evils.
As with all cases where you a...
Difference between a user and a schema in Oracle?
...other stuff.
SYS is a schema that includes tons of tables, views, grants, etc etc etc.
SYSTEM is a schema.....
Technically -- A schema is the set of metadata (data dictionary) used by the database,
typically generated using DDL. A schema defines attributes of the database, such as
tables, colum...
SQL update query using joins
...
UPDATE im
SET mf_item_number = gm.SKU --etc
FROM item_master im
JOIN group_master gm
ON im.sku = gm.sku
JOIN Manufacturer_Master mm
ON gm.ManufacturerID = mm.ManufacturerID
WHERE im.mf_item_number like 'STA%' AND
gm.manufacturerID = 34
To make it cl...
Read an Excel file directly from a R script
...at a time, although you can obviously loop over them all], included plots, etc.). But for a well-formed, rectangular spreadsheet with plain numbers and character data (i.e., not comma-formatted numbers, dates, formulas with divide-by-zero errors, missing values, etc. etc. ..) I generally have no pr...
Is Zookeeper a must for Kafka?
...d to have some way to coordinating tasks, state management, configuration, etc across a distributed system. Some projects have built their own mechanisms (think of the configuration server in a MongoDB sharded cluster, or a Master node in an Elasticsearch cluster). Others have chosen to take advanta...
How to access array elements in a Django template?
...ss individual elements of the array in the array (e.g. arr[0] , arr[1] ) etc. instead of looping through the whole array.
...
What is Ember RunLoop and how does it work?
...g else?
All of the basic user events (e.g. keyboard events, mouse events, etc) will fire up the run loop. This guarantees that whatever changes made to bound properties by the captured (mouse/keyboard/timer/etc) event are fully propagated throughout Ember's data-binding system before returning cont...
What is a correct mime type for docx, pptx etc?
...sions's MIME in a JSON format.
Just do example: MIME["ppt"], MIME["docx"], etc
{"x3d": "application/vnd.hzn-3d-crossword", "3gp": "video/3gpp", "3g2": "video/3gpp2", "mseq": "application/vnd.mseq", "pwn": "application/vnd.3m.post-it-notes", "plb": "application/vnd.3gpp.pic-bw-large", "psb": "applic...
What is difference between Errors and Exceptions? [duplicate]
... programmatically. Examples include FileNotFoundException, ParseException, etc. A programmer is expected to check for these exceptions by using the try-catch block or throw it back to the caller
On the other hand we have unchecked exceptions. These are those exceptions that might not happen if eve...
What is the difference between loose coupling and tight coupling in the object oriented paradigm?
...ul it would be to peel off your skin, dye it, and then to paste it back on etc? Changing your skin is difficult because it is tightly coupled to your body. You just can't make changes easily. You would have to fundamentally redesign a human being in order to make this possible.
Key Point #1: In o...