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How to use LINQ to select object with minimum or maximum property value
...be slower than the other solution suggested. However, if this is a LINQ to SQL table and DateOfBirth is an indexed column, then SQL Server will use the index instead of sorting all the rows. Other custom IEnumerable<T> implementations could also make use of indexes (see i4o: Indexed LINQ, or t...
Count work days between two dates
How can I calculate the number of work days between two dates in SQL Server?
23 Answers
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Django - limiting query results
...with no database access.
As you can see below your code only executes one sql query to fetch only the last 10 items.
In [19]: import logging
In [20]: l = logging.getLogger('django.db.backends')
In [21]: l.setLevel(logging.DEBUG)
In [22]: l...
SQLite - UPSERT *not* INSERT or REPLACE
...PLACE INTO Employee (id, role)
VALUES (1, 'code monkey');
GOOD: Use SQLite On conflict clause
UPSERT support in SQLite! UPSERT syntax was added to SQLite with version 3.24.0!
UPSERT is a special syntax addition to INSERT that causes the INSERT to behave as an UPDATE or a no-op if the INSERT ...
std::string length() and size() member functions
...ts, @Naveen, while fans of Perl's "There's more than one way to do it" (or SQL's syntax with a bazillion optional "noise words" giving umpteen identically equivalent syntactic forms to express one concept) will no doubt be complaining that Ruby, and especially C++, just don't go far enough in offeri...
Decimal precision and scale in EF Code First
...t I'm find out now that a property of type System.Decimal gets mapped to a sql column of type decimal(18, 0).
16 Answers
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@Basic(optional = false) vs @Column(nullable = false) in JPA
...d in
memory by the Persistence Provider and
an exception raised before SQL is sent
to the database otherwise when using
'updatable=false' 'optional'
violations would never be reported.
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ERROR: permission denied for sequence cities_id_seq using Postgres
...new at postgres (and at database info systems all in all). I ran following sql script on my database:
4 Answers
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How do I use a custom Serializer with Jackson?
...er should be something like this:
import java.io.IOException;
import java.sql.Timestamp;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.Serialize...
Hibernate: Automatically creating/updating the db tables based on entity classes
...ve.autodetection" value="class"/>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.format_sql" value="true"/>
<property name="hbm2ddl.auto" value="create-drop"/>
<!-- without below table was not created -->
<property name=...