BulkInsert

This method inserts all rows from the client application into the database in bulk. It is supported for Oracle.

This page documents the Oracle-specific arguments and examples. For the SQL Server implementation, see BulkInsert (SQL Server).

Use Case

Use this method to insert rows at high speed. It leverages the native bulk operation from ODP.NET via the OracleBulkCopy class, which always performs a direct-path load.

For inserting 1,000 or more rows, prefer this method over InsertAll.

Rows are written straight to the target table. A staging table is only used when identityBehavior is set to ReturnIdentity (see below) — see Operations (Oracle) for the underlying mechanics.

Special Arguments

The mappings, bulkCopyTimeout, batchSize, identityBehavior and pseudoTableType arguments are available for this operation.

mappings (via OracleBulkInsertMapItem) defines explicit column mappings between the source properties and the destination columns. When omitted, columns are auto-mapped by name (case-insensitive).

bulkCopyTimeout overrides the command timeout, in seconds.

batchSize overrides the number of rows sent to the server per batch. When not set, all items are sent at once.

identityBehavior (via OracleBulkImportIdentityBehavior) controls whether newly generated identity values are set back on the data entities. Disabled by default. Since Oracle does not support RETURNING ... BULK COLLECT INTO on an INSERT ... SELECT statement, enabling this routes the operation through a staging table instead, pre-generating identity values via the backing sequence’s NEXTVAL.

pseudoTableType (via OracleBulkImportPseudoTableType) controls the kind of staging table used when identityBehavior is ReturnIdentity.

Every pseudoTableType value currently resolves to Physical at runtime — see Operations (Oracle) for details.

Identity Setting Alignment

When identityBehavior is ReturnIdentity, the library adds a __RepoDb_OrderColumn column to the staging table to track each entity’s position in the source IEnumerable. This ensures the identity values returned from the database are assigned back to the correct entity via the compiled identity-setter function.

Usability

The following example defines a method that produces a list of Person objects, then bulk-inserts 10,000 rows into the Person table.

private IEnumerable<Person> GetPeople(int count = 1000)
{
    for (var i = 0; i < count; i++)
    {
        yield return new Person
        {
            Name = $"Person-{i}",
            SSN = Guid.NewGuid().ToString(),
            IsActive = true,
            DateInsertedUtc = DateTime.UtcNow
        };
    }
}

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = connection.BulkInsert(people);
}

To specify a batch size:

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = connection.BulkInsert(people, batchSize: 100);
}

When batchSize is not set, all rows are sent to the server in a single batch.

To return the newly generated identity values:

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = connection.BulkInsert(people,
        identityBehavior: OracleBulkImportIdentityBehavior.ReturnIdentity);
}

DataTable

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var table = ConvertToDataTable(people);
    var insertedRows = connection.BulkInsert("Person", table);
}

Dictionary/ExpandoObject

using (var sourceConnection = new OracleConnection(sourceConnectionString))
{
    var result = sourceConnection.QueryAll("Person");
    using (var destinationConnection = new OracleConnection(destinationConnectionString))
    {
        var insertedRows = destinationConnection.BulkInsert("Person", result);
    }
}

DataReader

using (var sourceConnection = new OracleConnection(sourceConnectionString))
{
    using (var reader = sourceConnection.ExecuteReader("SELECT * FROM Person"))
    {
        using (var destinationConnection = new OracleConnection(destinationConnectionString))
        {
            var rows = destinationConnection.BulkInsert("Person", reader);
        }
    }
}

To bulk-insert via DataEntityDataReader:

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    using (var reader = new DataEntityDataReader<Person>(people))
    {
        var insertedRows = connection.BulkInsert("Person", reader);
    }
}

Column Mappings

Add column mappings using the OracleBulkInsertMapItem class.

var mappings = new List<OracleBulkInsertMapItem>();

// Add the mappings
mappings.Add(new OracleBulkInsertMapItem("SourceId", "DestinationId"));
mappings.Add(new OracleBulkInsertMapItem("SourceName", "DestinationName"));
mappings.Add(new OracleBulkInsertMapItem("SourceIsActive", "DestinationIsActive"));
mappings.Add(new OracleBulkInsertMapItem("SourceDateInsertedUtc", "DestinationDateInsertedUtc"));

// Execute
using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = connection.BulkInsert(people,
        mappings: mappings);
}

Targeting a Table

To target a specific table, pass the literal table name.

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = connection.BulkInsert("Person", people);
}

Async Method

An equivalent BulkInsertAsync method is also available.

using (var connection = new OracleConnection(connectionString))
{
    var people = GetPeople(10000);
    var insertedRows = await connection.BulkInsertAsync(people);
}