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What's the difference between @JoinColumn and mappedBy when using a JPA @OneToMany association
...in physical information duplication (column name) along with not optimized SQL query that will produce some additional UPDATE statements.
According to documentation:
Since many to one are (almost) always the owner side of a bidirectional relationship in the JPA spec, the one to many association is...
What is the best way to implement nested dictionaries?
... @jason Depending on the data, I like to use JSON, csv files, or even a sqlite database to store it.
– nosklo
Feb 12 '19 at 6:37
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Why JSF saves the state of UI components on server?
...mory in flavor of a session scoped bean where Java is been used instead of SQL to filter/group/arrange the records. With ~1000 records, that would easily go over 10MB per user session.
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Do try/catch blocks hurt performance when exceptions are not thrown?
...c language features to behave correctly, and optimize what we can control (sql, indexes, algorithms).
– Kobi
Aug 22 '09 at 16:13
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How does the Amazon Recommendation feature work?
...ed out in commerce server) have moved on to live directly within Microsoft SQL.
The four big take-a-ways you should have are:
Amazon (or any retailer) is looking at aggregate data for tons of transactions and tons of people... this allows them to even recommend pretty well for anonymous users o...
MySQL vs MongoDB 1000 reads
...t MongoDb and have been testing it lately. I had a table called posts in MySQL with about 20 million records indexed only on a field called 'id'.
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Is VB really case insensitive?
...ase sensitive. String comparisons are usually case sensitive, unlike say T-SQL, but there are compiler switch to make string comparisons case insensitive. And of course there are the edge cases when dealing with inheritance, COM, and Dynamic Language Runtime.
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How do you do Impersonation in .NET?
... types. LOGON32_LOGON_INTERACTIVE was the first enum value that worked for sql server. My connection string was just trusted. No user name / password in the connection string.
<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
Public Class Impersonation
Implements IDisposable...
Entity Framework DateTime and UTC
...tatype. This will store the time zone with the date value in the database (SQL Server 2015 in my case).
When EF Core requests the data from the DB it will receive the timezone info as well.
When you pass this data to a web application (Angular2 in my case) the date is automatically converted to the...
Why is String immutable in Java?
...ble. *** Example - Name one technique to attack the DB of a web app --> SQL Injection. Do you know any techniques like this for attacking the references ?
– MasterJoe
Jul 25 '18 at 17:31
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