ADO.NET 2.0 SQLite Data Provider
Version 1.0.10 - June 10, 2005
Interop using SQLite 3.22
Written by Robert Simpson (firstname.lastname@example.org)
Released to the public domain, use at your own risk!
This provider was written and verified using the Visual Studio 2005 Beta 2
The latest version can be downloaded
DbProviderFactory support, just add the XML below at the machine.config and/or
Full support for ATTACH'ed databases. Exposed as Catalogs
in the schema. When cloning a connection, all attached databases are
automatically re-attached to the new connection.
DbConnection.GetSchema(...) support includes the MetaDataCollections, DataSourceInformation,
Columns, Tables, Views, Catalogs and Indexes
Enhanced DbDataReader.GetSchemaTable() functionality returns catalog, namespace
and detailed schema information even for complex queries.
Named and unnamed parameters.
Full UTF-8 and UTF-16 support.
Multiple simultaneous DataReaders (one DataReader per Command however).
Full support for user-defined scalar and aggregate functions, encapsulated into
an easy-to-use base class in which only a couple of overrides are necessary to
implement new SQL functions.
Full support for user-defined collating sequences, every bit as simple to
implement as user-defined functions and uses the same base class.
In order to use the SQLiteFactory and have the SQLite data provider enumerated
in the DbProviderFactories methods, you must add the following segment into
either your application's app.config or the system's machine.config located in
the %SystemRoot%\Microsoft.Net\Framework\v2.xxxx\Config folder:
<add name="SQLite Data Provider" invariant="System.Data.SQLite" support="3F" description=".Net Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
Compiling for the Compact Framework
The SQLite.Interop.DLL does not (yet) support a build that includes Windows CE
processor architectures. I am aware of the CE port of SQLite and will be
investigating their code to see how best to proceed in that regard. I am
also waiting for the newer version of SQLite to become available which will
offer select metadata information and will cause a major redesign of this
library to support it.
Development Notes Regarding the SQLite 3 Source Code
Steps for merging the sqlite3 core codebase:
Download the latest sqlite3 source from
Extract the source code to the SQLite.Interop\src
directory of this project
Open the src\select.c
Add #include "../interop.h"
to the top of the file where the other include's are.
Scroll down the select.c file to around line 748. Change
the name of the function static void generateColumnNames to static void
_generateColumnNames (note the underscore in front of the name).
1.10 - June 10, 2005
1.09a - May 25, 2005
Fixed a bug in the SQLite3.cs Prepare() function that created a statement even
when the SQLite engine returned a NULL pointer. Typically this occurs when
multiple statements are processed and there are trailing comments at the end of
Fixed a bug in SQLiteStatement.cs that retrieved parameter names for a
parameterized query. SQLite's parameters are 1-based, and the function
was starting at 0. This was fine when all parameters were unnamed, but
for named parameters it caused the parameters to be out of whack.
1.09 - May 24, 2005
Fixed a broken helpfile and corrected some obsolete help remarks in
- Added a version resource to the SQLite.Interop.DLL.
1.08 Refresh - Mar 24, 2005
Code merge with the latest 3.21 version of SQLite.
Removed obsolete methods and properties for Whidbey Beta 2
1.08 - Mar 11, 2005
Code merge with the latest 3.20 version of SQLite.
Recompiled the help file to fix a build error in it.
1.07 - Mar 5, 2005
Added additional #if statements to support the old beta 1 edition of VS2005.
Code merged the SQLite 3.14 source.
Made more optimizations to frequently-called functions, resulting in
significant performance gains in all tests.
Recompiled the binaries using the latest VS2005 February CTP, resulting in yet
more significant speed gains. The 100k insert test used to take 3.5
seconds and the insertwithidentity took almost 8 seconds. With the above
two changes, those tests are now executing in 1.9 and 4.9 seconds respectively.
1.06 - Mar 1, 2005
Speed-ups to SQLiteDataReader. It was interop'ing unnecessarily every
time it tried to fetch a field due to a logic error.
Changed/Added some code to SQLiteConvert's internal DbType, Type and
Fixed the SQLiteDataReader to obey the flags set in the optional
CommandBehavior flag from SQLiteCommand.ExecuteReader().
Changed the default page size to 1024 to reflect the defaults of SQLite.
Ignores the "Page Size" connection string option for memory databases, as tests
revealed that changing it resulted in memory corruption errors.
Performance enhancements to the SQLiteCommand and SQLiteStatement classes which
reduced the 100,000 row insert execution time as well as the various Function
execution times significantly.
1.05 - Feb 25, 2005
Fixed the SQLite3 C# class step/reset functions to accomodate schema changes
that invalidate a prepared statement. Statements are recompiled
Moved all native DLL declarations to an UnsafeNativeMethods class.
Split several classes into their own modules for readability.
Renamed many internal variables, reviewed access to variables marked as
internal and altered their protection levels accordingly.
Due to the presence of the altered sqlite3 codebase and so many added interop
functions, I decided to rename the sqlite3 C project and the DLL to
SQLite.Interop.DLL. This is the same core sqlite3 codebase but designed
specifically for this ADO.NET provider. This eliminates any possibility
of someone dropping another build of sqlite3.dll into the system and rendering
the provider inoperable. In the future if the folks at sqlite.org finally
introduce a method of retrieving column usage for an arbitrary prepared
statement, I'll retool this library to be a lightweight function call wrapper
around the core binary distribution.
Added [SuppressUnmanagedCodeSecurity] attribute to the UnsafeNativeMethods
class which brings VS2005 November CTP execution speeds inline with the
Added a bin
directory to the project root where pre-compiled binaries can be found.
Added a doc
directory where preliminary documentation on the class library can be found.
Documented a lot more of the classes internally.
1.04 - Feb 24, 2005
1.03 - Feb 23, 2005
Removed the SQLiteContext class and revamped the way UserFunctions work to
simplify the imlementation.
Fixed a counting bug in the TestCases class, specifically in the function tests
where I wasn't resetting the counter and it was consequently reporting
intrinsic and raw select calls as being much much faster than they actually
were. The numbers are now much closer to what I expected for performance,
with .NET user-functions still being the slowest, but only by a small margin.
Small performance tweaks to SQLiteDataReader.
Added PageSize to the SQLiteConnectionStringBuilder and subsequently to the
Added a PRAGMA encoding=XXX execution statement to the SQLiteConnection after
opening a connection.
Fixed up SQLiteCommandBuilder to correct implementation errors, which resulted
in an enormous performance boost in the InsertMany test. 10,000 row
insert that executed in 1500ms now executes in 500ms.
Fixed several errors in the SQLite3_UTF16 class. ToString() was working
incorrectly and the Open() method failed to register user defined functions and
Fixed a bug in SQLiteCommand.ClearCommands() whereby only the first statement
was being properly cleaned up.
Fixed a bug in SQLiteDataReader whereby calling NextResult() would not properly
reset the previously-executed command in the sequence.
Added an InsertManyWithIdentityFetch test, which appends a select clause to
populate the ID of the last inserted row into the InsertCommand, demonstrating
ADO.NET's ability to auto-fetch identity columns on insert.
1.02 - Feb 21, 2005
Tweaks to the xxx_interop functions that return char *'s, so they also return
the length. Saves an interop call to get the UTF-8 string length during
conversion to a .NET string.
Reworked the whole interop.c thing into interop.h and reduced the code required
to merge the main sqlite3 codebase.
Added support for user-defined collations.