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How big is too big for a PostgreSQL table?
...,1 as c2,2 as c3
from generate_series(1,90000000) x;
https://wiki.postgresql.org/wiki/FAQ
Limit Value
Maximum Database Size Unlimited
Maximum Table Size 32 TB
Maximum Row Size 1.6 TB
Maximum Field Size 1 GB
Maximum Rows per Table Unlimited
Maximum Columns...
Examples of GoF Design Patterns in Java's core libraries
...nd - TextComponent's Undo/Redo.
Interpreter - RegEx (java.util.regex.) and SQL (java.sql.) API.
Prototype - Not 100% sure if this count, but I thinkg clone() method can be used for this purpose.
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What is causing ERROR: there is no unique constraint matching given keys for referenced table?
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In postgresql all foreign keys must reference a unique key in the parent table, so in your bar table you must have a unique (name) index.
See also http://www.postgresql.org/docs/9.1/static/ddl-constraints.html#DDL-CONSTRAINTS-FK and s...
How to add a line break in C# .NET documentation
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/// <summary>
/// <para>Get a human-readable variant of the SQL WHERE statement of the search element.</para>
/// Rather than return SQL, this method returns a string with icon-tokens, which
/// could be used to represent the search in a condensed pictogram format.
/// </sum...
PHP function to build query string from array
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Implode will combine an array into a string for you, but to make an SQL query out a kay/value pair you'll have to write your own function.
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Hibernate Annotations - Which is better, field or property access?
...a is to shy away from ORM solutions altogether. Learn how to write proper SQL.
– duffymo
May 27 '16 at 16:44
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JPA EntityManager: Why use persist() over merge()?
...ached, entityToSave);
return attached;
}
Although if connected to MySQL merge() could be as efficient as persist() using a call to INSERT with ON DUPLICATE KEY UPDATE option, JPA is a very high level programming and you can't assume this is going to be the case everywhere.
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Use of Application.DoEvents()
...reen (How to display a "loading" overlay...) updated during a long running SQL command:
IAsyncResult asyncResult = sqlCmd.BeginExecuteNonQuery();
while (!asyncResult.IsCompleted) //UI thread needs to Wait for Async SQL command to return
{
System.Threading.Thread.Sleep(10);
Application...
Entity Framework rollback and remove bad migration
...command:
PM> get-help entityframework
Refreshing dastabase in VS2015 SQL Server Object Explorer, all of my data was preserved and the migration that I wanted to revert was gone :)
Initially I tried Remove-Migration by itself and found the error command confusing:
System.InvalidOperationEx...
Good ways to sort a queryset? - Django
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I just wanted to illustrate that the built-in solutions (SQL-only) are not always the best ones. At first I thought that because Django's QuerySet.objects.order_by method accepts multiple arguments, you could easily chain them:
ordered_authors = Author.objects.order_by('-score', ...