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Is there a VB.NET equivalent for C#'s '??' operator?
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You can use an extension method. This one works like SQL COALESCE and is probably overkill for what you are trying to test, but it works.
''' <summary>
''' Returns the first non-null T based on a collection of the root object and the args.
''' </summary>...
How do I ALTER a PostgreSQL table and make a column unique?
I have a table in PostgreSQL where the schema looks like this:
3 Answers
3
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Why does “_” (underscore) match “-” (hyphen)?
...dcard like the percent %, except that it only looks for one character.
SQL pattern matching enables you to use "_" to match any single character and "%" to match an arbitrary number of characters (including zero characters).
(From section 3.3.4.7. Pattern Matching in the MySQL documentation.)
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Why do we need Abstract factory design pattern?
...a sources. Assume your application supports different data stores. (e.g. a SQL Database and an XML file). You have two different data access interfaces e.g. an IReadableStoreand IWritableStore defining the common methods expected by your application regardless of the type of data source used.
Which...
Java: Date from unix timestamp
...er compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, and later
Built-in.
Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Jav...
The maximum recursion 100 has been exhausted before statement completion
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List of Rails Model Types
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The attributes are SQL types, hence the following are supported:
:binary
:boolean
:date
:datetime
:decimal
:float
:integer
:primary_key
:string
:text
:time
:timestamp
These are documented under column in the Active Record API.
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in a “using” block is a SqlConnection closed on return or exception?
...even for the new maintenance programmer who will support it later:
using (SqlConnection connection = new SqlConnection(connectionString))
{
int employeeID = findEmployeeID();
try
{
connection.Open();
SqlCommand command = new SqlCommand("UpdateEmployeeTable",...
What is wrong with using goto? [duplicate]
...gramming, as I've just discovered when trying to make a loop continue in T-SQL.
– Denziloe
Feb 19 '19 at 16:35
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Using union and order by clause in mysql
I want to use order by with union in mysql query.
I am fetching different types of record based on different criteria from a table based on distance for a search on my site.
The first select query returns data related to the exact place search .
The 2nd select query returns data related to distance ...