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Common programming mistakes for Clojure developers to avoid [closed]
...boolean java-bool) "Yes" "No").
I got burned by this with clojure.contrib.sql library that returns database boolean fields as java Boolean objects.
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Why do we need boxing and unboxing in C#?
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true - it shows up all the time in ADO.NET too - sql parameter values are all 'object's no matter what the real data type is
– Ray
Jan 21 '10 at 19:12
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MongoDB: Combine data from multiple collections into one..how?
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Doing unions in MongoDB in a 'SQL UNION' fashion is possible using aggregations along with lookups, in a single query. Here is an example I have tested that works with MongoDB 4.0:
// Create employees data for testing the union.
db.getCollection('employe...
Is Python strongly typed?
... Short, crisp and to the point answer
– sql_learner
yesterday
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Git vs Team Foundation Server [closed]
...ogy around -- imagine you need a serious relational database. You evaluate Sql Server, Oracle, and MS Access. You end up choosing Access because it has the nicest GUI, in spite of the fact that it can't scale, doesn't enforce referential integrity very well, etc. Branching and Merging are the absolu...
What is the difference between partitioning and bucketing a table in Hive ?
... querying the data. For example, in the above table, if we write the below sql, it need to scan all the records in the table which reduces the performance and increases the overhead.
select * from sales_table where product_id='P1'
To avoid full table scan and to read only the records related to p...
Simple explanation of MapReduce?
...taset can then be reduced to a scalar value.
So if you think of it like a SQL statement
SELECT SUM(salary)
FROM employees
WHERE salary > 1000
GROUP by deptname
We can use map to get our subset of employees with salary > 1000
which map emits to the barrier into group size buckets.
Reduce ...
Why Qt is misusing model/view terminology?
... model you are using (own model subclass: probably within the model; e.g. QSqlTableModel: outside (but maybe cached within) the model). To put your models and views together, use own classes which then implement the business logic.
Long answer
Qt's model/view approach and terminology:
Qt provid...
What is the difference between JSON and Object Literal Notation?
...tion in the language itself. It is derived from a single language.
SQL Language - Hibernate MySQL Dialect, Oracle Dialect,.. which have some changes or added functionality.
Information about the browser and computer of your users.
navigator.appName // "Netscape"
ECMAScript is the scr...
What column type/length should I use for storing a Bcrypt hashed password in a Database?
...ectively.
As you use the 2a format, you’ll need 60 bytes. And thus for MySQL I’ll recommend to use the CHAR(60) BINARYor BINARY(60) (see The _bin and binary Collations for information about the difference).
CHAR is not binary safe and equality does not depend solely on the byte value but on the ...