See Making Other Kinds Of Table Schema Changes in the SQLite documentation for more details. You will need to use the Sql(string) method to perform some of these steps. Table rebuilds involve creating a new table, copying data to the new table, dropping the old table, renaming the new table.
SQLITE SCHEMA CODE
You can workaround some of these limitations by manually writing code in your migrations to perform a rebuild. If a database artifact isn't part of the model-for example, if it was created manually inside a migration-then a NotSupportedException is still thrown. Rebuilds are only possible for database artifacts that are part of your EF Core model. If you attempt to apply one of the unsupported operations to a SQLite database then a NotSupportedException will be thrown.Ī rebuild will be attempted in order to perform certain operations. The SQLite database engine does not support a number of schema operations that are supported by the majority of other relational databases. You can use a value converter to continue using decimal in your classes. If you don't need that level of precision, however, we recommend using double instead. The Decimal type provides a high level of precision. When handling multiple time zones, we recommend converting the values to UTC before saving and then converting back to the appropriate time zone. Instead of DateTimeOffset, we recommend using DateTime values. Other operations, however, like comparison and ordering will require evaluation on the client. EF Core can read and write values of these types, and querying for equality ( where e.Property = value) is also supported. SQLite doesn't natively support the following data types. A couple of these concepts are not supported by the SQLite provider.
The common relational library (shared by Entity Framework relational database providers) defines APIs for modelling concepts that are common to most relational database engines. Most of these limitations are a result of limitations in the underlying SQLite database engine and are not specific to EF. SELECT t.name AS tbl_name, c.name, c.type, c.notnull, c.dflt_value, c.The SQLite provider has a number of migrations limitations. Instead, you can query directly for schema information using the sqlite_master table and PRAGMA statements like table_info and foreign_key_list.įor example, this query will retrieve metadata about all the columns in the database. doesn't implement the GetSchema method on DbConnection. Post.id AS post_id INTEGER PRIMARY KEY AUTOINCREMENT If (column as bool? = true)įor example, this query would produce the following debug string: SELECT id AS post_id, Var schemaTable = reader.GetSchemaTable() įoreach (DataRow column in schemaTable.Rows)
SQLITE SCHEMA HOW TO
The following example shows how to use GetSchemaTable to create a debug string that shows metadata about a result: var builder = new StringBuilder() True if the origin column is part of the PRIMARY KEY.Īlways NULL. True if the column originates from an expression in the query. True if the origin column was created with the AUTOINCREMENT keyword. True if the column name is aliased in the result set. The ordinal of the column in the result set.Īlways -1. The name or alias of the column in the result set. The path to the database file specified in the connection string. The name of the origin column's database. The returned DataTable contains the following columns: Column You can retrieve metadata about the results of a query using the GetSchemaTable method on SqliteDataReader. The other retrieves metadata about the database schema. One retrieves metadata about query results. There are two APIs for retrieving metadata in ADO.NET.
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