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“Insert if not exists” statement in SQLite
... and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert op...
Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
MySQL case sensitive query [duplicate]
...ing for 'value'. However it will return 'VALUE', 'value', 'VaLuE', etc…
SELECT * FROM `table` WHERE `column` = 'value'
The good news is that if you need to make a case-sensitive query, it is very easy to do using the BINARY operator, which forces a byte by byte comparison:
SELECT * FROM `table...
Literal suffix for byte in .NET?
...t
does 0xFFB mean?) and even if we had a solution for that, or another
character than 'B' ('Y' was considered, F# uses this) no one could
remember whether the default was signed or unsigned - .NET bytes are
unsigned by default so it would make sense to pick B and SB but all
the other suffi...
How do I return to an older version of our code in Subversion?
...
If you are using TortoiseSVN, right-click the file select Merge, then Merge a Range of Revisions. In the log box type in 140-150 and click the Reverse Checkbox. After that, commit as usual. This will perform the same operation as Jon's example.
– DavGarc...
How to load assemblies in PowerShell?
...me;
These should also work:
Add-Type -AssemblyName $TypeName -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
If I want my script to always use a specific version of a .dll but I can't be certain of where it's installed, how do I determine what ...
What is the effect of encoding an image in base64?
...e64 is the better choice.
Size of base64-images
Base64 uses 64 different characters and this is 2^6. So base64 stores 6bit per 8bit character. So the proportion is 6/8 from unconverted data to base64 data. This is no exact calculation, but a rough estimate.
Example:
An 48kb image needs around 64...
Hibernate dialect for Oracle Database 11g?
...e getQuerySequencesString() method, that returns this query:
"select sequence_name from user_sequences;"
for which the execution returns an empty result from database).
Using the dialect org.hibernate.dialect.Oracle9iDialect , or greater, solves the problem, due to a di...
Proper Repository Pattern Design in PHP?
...
public function fetch($fields)
{
return $this->db->select($fields)->from('users')->orderBy('last_name, first_name')->rows();
}
}
Before moving on to the controller, I want to show another example to illustrate how powerful this is. Maybe I have a reporting engi...
What does the @ symbol represent in objective-c?
...
The @ character isn't used in C or C++ identifiers, so it's used to introduce Objective-C language keywords in a way that won't conflict with the other languages' keywords. This enables the "Objective" part of the language to free...