Simple.Data

Simple.Data defines a number of commands for retrieving data from a data store. These can then be daisychained in a LINQ-like fashion with further methods to modify the basic query.

FindBy

FindBy is now deprecated in favour of using FindAllBy.FirstOrDefault() or Get. More details here.

FindBy returns a single row of data as a SimpleRecord object based on at least one column name and value to filter by; if more than one row matches, the first row retrieved from the data store is returned.

There are two ways to form a FindBy method.

You can specify the column names as named parameters.
You can specify the column names as part of the method

Syntax

public SimpleRecord FindBy(
		Object[] filterExpressions
	)

public SimpleRecord FindBycolumnName1[AndcolumnName2…](
	Object columnValue1
	[, Object columnValue2]
)

Parameters

filterExpressions: Type: object[]
A set of named parameters where the parameter name is that of column being filtered against and the parameter value is that which the column should equal.
columnName1[, columnName2, …, columnNameX]: Type: string The name of the column(s) being filtered against
columnValue1[, columnValue2, …, columnValueX]: Type: object (typically string or int) columnValueY contains the value with which column with name columnNameY should equal.

Return Value

Type: SimpleRecord
An object containing a property for each of the columns requested by Simple.Data whose values are those of the single row retrieved from the data store.

Exceptions

Exception	Condition
`ArgumentException`	You have specified no named parameters for `filterExpressions` -or- The number of `columnNames` does not match the number of `columnValues`
`NullReferenceException`	One of the `columnValues` has been set to `null`

Remarks

FindBy is used to return data from a table based on a set of criteria where the value of columns in a row

are equal to given values - e.g. Artistid=6 and Title="Back in Black"
are within certain sets of values, a range or an array. See the Where clause page for more information.

If you wish to include a column name in a filter that contains the string “and” in it, you must use the named parameter form of FindBy. If you have a column called, for example, HandlingCode, and you try to call

FindByHandlingCode(1);

the parser will split that into two columns, H & lingCode, and throw an ArgumentException. So you have to use the named parameter form for columns with “and” in the name. For example,

FindBy(HandlingCode:1);

Examples

The following example retrieves the first album with GenreId equal to 1 and outputs its title to the Console window.

var album = Database.Open().Albums.FindByGenreId(1);
	
// The named parameter equivalent call to FindBy() is
// var album = Database.Open().Albums.FindBy(GenreId:1);
	
Console.WriteLine(album.Title);

Simple.Data sends the following SQL to the database when album is evaluated.

SELECT TOP 1 
    [dbo].[Album].[AlbumId], 
    [dbo].[Album].[GenreId], 
    [dbo].[Album].[ArtistId], 
    [dbo].[Album].[Title], 
    [dbo].[Album].[Price], 
    [dbo].[Album].[AlbumArtUrl] 
from [dbo].[Album]  
where 
    [dbo].[Album].[GenreId] = @p1
@p1 (Int32) = 1

The following example retrieves the first album with GenreId equal to 1 and ArtistId equal to 120 and outputs its title to the Console window.

var album = Database.Open().Albums.FindByGenreIdAndArtistId(1,120);
	
// The named parameter equivalent call to FindBy() is
// var album = Database.Open().Albums.FindBy(GenreId:1,ArtistId:120);
	
Console.WriteLine(album.Title);

Simple.Data sends the following SQL to the database when album is evaluated.

SELECT TOP 1 
    [dbo].[Album].[AlbumId], 
    [dbo].[Album].[GenreId], 
    [dbo].[Album].[ArtistId], 
    [dbo].[Album].[Title], 
    [dbo].[Album].[Price], 
    [dbo].[Album].[AlbumArtUrl] 
from [dbo].[Album]  
where 
    ([dbo].[Album].[GenreId] = @p1 AND [dbo].[Album].[ArtistId] = @p2)
@p1 (Int32) = 1
@p2 (Int32) = 120