If a column is declared as a DATE or DATETIME, SqliteDataReader will try to turn the value back into a DateTime. Sqlite3 also exposes the names of the types of the columns as the table was created with. But this doesn’t help when reading the data back to determine that a value was originally a DateTime. When putting a DateTime into the database using parameters, will encode the DateTime as an integer using ToFileTime(). Sqlite3 has string, integer (64bit), real, and blob internal storage types. If you explicitly are targetting Sqlite3, or using the new assembly (in which case you should be providing the version parameter in the connection string, unless you are using the new assembly), you can rely on the particular behavior used when connecting to a Sqlite3 database. Using Sqlite2, you really can’t use DateTimes without encoding them yourself. When reading back the data, there’s no way to know that it was originally a DateTime and not a string, so returns the string. If you use parameters, for instance, DateTimes will be converted in a culture-sensitive format. No matter what the column was declared as, DateTimes are just going to be converted into strings. The recommended way of using DateTimes with Sqlite is to encode/decode them yourself to/from some particular integer string format that you decide, and not putting them into a DATE or DATETIME column. Further, there are two versions of Sqlite (2 and 3) which are treated differently when it comes to DateTimes. The way DateTimes are stored and retrieved from Sqlite databases depends on a lot, unfortunately, because Sqlite doesn’t have a way of storing datetimes natively. The default value is 0, which means to throw a SqliteBusyException immediately if the database is locked.įor the 2.0 profile in the new assembly Parameter Definition The busy_timeout parameter is implemented as a call to sqlite(3)_busy_timeout. Version of SQL Lite to use: version 2 or 3Ī timeout, in milliseconds, to wait when the database is locked before throwing a SqliteBusyException (since Mono 1.1.14) The new assembly, as described above, uses only database format version 3.įor the 1.1 profile and the old assembly Parameter Definition You can force the adapter to use version 3 by adding “version=3” to the connection string: URI=file:SqliteTest.db,version=3 With the old assembly, the ADO.NET adapter will use SQLite version 2 by default, but if version 2 is not found and version 3 is available, it will fallback to version 3. The version=3 is supported, but not necessary with the new assembly. Or you prefer to use SQLite as an in memory database URI=file::memory:,version=3 That will use the database SqliteTest.db in the current directory. The latter case for the 2.0 profile references the App_Data directory (or any other directory that’s configured to contain data files for an ASP.NET 2.0 application)Īs an example: so along side your application binaries, or in a system-wide library path. There are binaries for Windows and Linux. To solve this problem you must dump your data using sqlite v2 utilities and then restore it using sqlite v3 utilities. That is, if your application uses SQLite database v2 format you will not be able to access your data with the new assembly. One disadvantage of the new assembly is its binary incompatibility in the data format. All the developers are encouraged to start transitioning their code to the new assembly - for both 1.1 and 2.0 profiles. NET applications - both assemblies will be shipped with several future releases of Mono, and at some (yet undetermined) point the old one will be removed from the distribution. We have chosen this way as means to provide a migration path for developers using SQLite in their. The 2.0 profile can no longer access the old code when referencing the new assembly. Code from the old binary is contained in the new one but is available only in the 1.1 profile. The new assembly is based on code by Robert Simpson from and provides full ADO.NET 2.0 API interface. The new assembly provides support only for SQLite version 3and is not 100% binary and API compatible with the older assembly. Starting with the 1.2.4 release, Mono ships a second SQLite assembly. New style assembly shipped with Mono 1.2.4 6 C# Example (1.1 profile of the new assembly and the old assembly).1 New style assembly shipped with Mono 1.2.4.See below for notes on storing DateTimes. So you need to be careful about avoiding casting values returned by SQLite without checking the type of the value returned. And in SQLite version 2, everything is stored as a string. Everything is stored as either a long, double, string, or blob. SQLite has a notable oddity: table cell data does not retain what kind of data it was. The assembly contains an ADO.NET data provider for the SQLite embeddable database engine (both version 2 and version 3).
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