BulkInsert

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

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

Call Flow Diagram

The diagram below shows the flow when calling this operation.

flowchart TD
    Client["Client<br/>(RepoDB)"] -->|BulkInsert| Source["Entities /<br/>DataTable /<br/>DbDataReader"]
    Source --> Decision{"identityBehavior ==<br/>ReturnIdentity?"}
    Decision -->|NO| Direct["FirebirdCommandBatcher<br/>(FbBatchCommand)"]
    Direct -->|Write| Table[("Target Table")]
    Decision -->|YES| Pseudo["Create Pseudo Table<br/>(Auto/Memory/Physical) +<br/>client-assigned row-order column"]
    Pseudo --> Staged["FirebirdCommandBatcher<br/>(FbBatchCommand)"]
    Staged -->|Write| PseudoTable[("Pseudo Table")]
    PseudoTable --> Insert["EXECUTE BLOCK:<br/>FOR SELECT ... FROM Pseudo<br/>ORDER BY row-order DO<br/>INSERT INTO Target ... RETURNING id INTO :R0; SUSPEND"]
    Insert --> Table
    Insert -->|"assign identities back<br/>to entities, in row-order"| Client
    PseudoTable -->|Drop| Cleanup(["Pseudo Table Dropped"])

Use Case

Use this method to insert rows at high speed. It leverages FbBatchCommand, the FirebirdSql.Data.FirebirdClient driver’s native ADO.NET batching API, via FirebirdCommandBatcher.

For inserting 1,000 or more rows, prefer this method over InsertAll — Firebird’s IsMultiStatementExecutable setting is false, so InsertAll issues one round trip per row, while this method batches many rows per round trip.

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

Special Arguments

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

mappings (via FirebirdCommandBatcherMapItem) defines explicit column mappings between the source properties and the destination columns, with an optional FbDbType override per mapping. When omitted, columns are auto-mapped by name (case-insensitive).

bulkCopyTimeout overrides the command timeout, in seconds. FbBatchCommand has no timeout-equivalent property, so this argument currently has nothing to apply to.

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

identityBehavior (via FirebirdBulkImportIdentityBehavior) controls whether newly generated identity values are set back on the data entities. Disabled (KeepIdentity) by default. Enabling this (ReturnIdentity) routes the operation through a pseudo table instead, reading the generated identity values back via an EXECUTE BLOCK loop of INSERT ... RETURNING.

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

The DbDataReader overload has no identityBehavior argument — a forward-only, single-pass reader cannot be rewound to correlate generated identity values back onto a source row, so ReturnIdentity is not supported for that overload.

Identity Setting Alignment

When identityBehavior is ReturnIdentity, the library assigns a client-side, zero-based row-order value onto a copy of the source rows before staging them, rather than relying on a server-generated ordering column. The staged rows are then fed into the real INSERT via an EXECUTE BLOCK cursor loop ordered by that row-order column, and the generated identity from each RETURNING ... INTO :R0 is assigned back to the correspondingly-positioned entity as the loop’s result set is read.

Because the row order is explicitly assigned client-side rather than inferred by sorting the generated identity values themselves, this correlation does not depend on an unverified ordering assumption the way some other providers’ FINAL TABLE-based approaches do.

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}",
            Age = 30,
            CreatedDateUtc = DateTime.UtcNow
        };
    }
}

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

To specify a batch size:

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

DataTable

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

Dictionary/ExpandoObject

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

DataReader

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

To bulk-insert via DataEntityDataReader:

using (var connection = new FbConnection(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 FirebirdCommandBatcherMapItem class.

var mappings = new List<FirebirdCommandBatcherMapItem>();

// Add the mappings
mappings.Add(new FirebirdCommandBatcherMapItem("SourceId", "DestinationId"));
mappings.Add(new FirebirdCommandBatcherMapItem("SourceName", "DestinationName"));
mappings.Add(new FirebirdCommandBatcherMapItem("SourceAge", "DestinationAge"));
mappings.Add(new FirebirdCommandBatcherMapItem("SourceCreatedDateUtc", "DestinationCreatedDateUtc"));

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

Async Method

An equivalent BulkInsertAsync method is also available.

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