BulkUpdate

This method updates existing rows in the database in bulk, matched by the defined qualifiers. It is supported for EnterpriseDB.

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

Call Flow Diagram

The diagram below shows the flow when calling this operation.

flowchart TD
    Client["Client<br/>(RepoDB)"] -->|BulkUpdate| Source["Entities /<br/>DataTable /<br/>DbDataReader"]
    Source --> Guard{"Any updateable<br/>field left after<br/>excluding qualifiers?"}
    Guard -->|NO| Skip["Return 0<br/>(no pseudo table created)"]
    Guard -->|YES| Pseudo["Create Pseudo Table<br/>(Auto/Memory/Physical) +<br/>Index on qualifiers"]
    Pseudo --> Loader["EDBBulkCopy<br/>(Npgsql binary COPY)"]
    Loader -->|Write| PseudoTable[("Pseudo Table")]
    PseudoTable -->|"UPDATE Target SET ...<br/>FROM Pseudo S<br/>WHERE (qualifiers match)"| Table[("Target Table")]
    PseudoTable -->|Drop| Cleanup(["Pseudo Table Dropped"])

Use Case

Use this method to update rows against EnterpriseDB at high speed. It leverages RepoDb.Connector.EnterpriseDb’s EDBBulkCopy, itself built on top of Npgsql’s native binary COPY protocol — a genuine bulk load, not a client-side loop of single-row statements.

A pseudo (staging) table, indexed on the qualifier columns, is created for every call and dropped afterward. The library writes to it via EDBBulkCopy, then cascades the changes to the target table via an UPDATE ... FROM join — see Operations (EnterpriseDB) for the underlying mechanics.

Unlike BulkMerge, staged rows with no matching target row are left as-is, not inserted.

Special Arguments

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

qualifiers defines the fields used to match existing rows, corresponding to the WHERE clause. Defaults to the primary or identity column if not specified.

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

bulkCopyTimeout overrides the command timeout, in seconds, applied to the underlying EDBBulkCopy write while staging.

batchSize overrides the number of rows written per batch. When not set, the provider’s default batch size is used.

pseudoTableType (via EDBBulkImportPseudoTableType) controls the kind of staging table used — Auto (default) picks Physical once the row count reaches the internal threshold (5000), otherwise Memory.

If every staged field is also a qualifier (nothing left to actually update), the operation returns 0 immediately — no pseudo table is created at all.

Usability

Given a list of Person models, the following example bulk-updates rows in the Person table.

using (var connection = new EDBConnection(connectionString))
{
    var updatedRows = connection.BulkUpdate(people);
}

Or with qualifiers:

using (var connection = new EDBConnection(connectionString))
{
    var updatedRows = connection.BulkUpdate(people, qualifiers: e => new { e.LastName, e.DateOfBirth });
}

To specify a batch size:

using (var connection = new EDBConnection(connectionString))
{
    var updatedRows = connection.BulkUpdate(people, batchSize: 100);
}

DataTable

using (var connection = new EDBConnection(connectionString))
{
    var table = ConvertToDataTable(people);
    var updatedRows = connection.BulkUpdate("\"Person\"", table);
}

Dictionary/ExpandoObject

using (var sourceConnection = new EDBConnection(sourceConnectionString))
{
    var result = sourceConnection.QueryAll("\"Person\"");
    using (var destinationConnection = new EDBConnection(destinationConnectionString))
    {
        var updatedRows = destinationConnection.BulkUpdate("\"Person\"", result,
            qualifiers: Field.From("Name"));
    }
}

DataReader

using (var sourceConnection = new EDBConnection(sourceConnectionString))
{
    using (var reader = sourceConnection.ExecuteReader("SELECT * FROM \"Person\" WHERE \"Age\" > 18"))
    {
        using (var destinationConnection = new EDBConnection(destinationConnectionString))
        {
            var updatedRows = destinationConnection.BulkUpdate("\"Person\"", reader);
        }
    }
}

To bulk-update via DataEntityDataReader:

using (var connection = new EDBConnection(connectionString))
{
    var people = GetPeople(10000);
    using (var reader = new DataEntityDataReader<Person>(people))
    {
        var updatedRows = connection.BulkUpdate("\"Person\"", reader);
    }
}

Field Qualifiers

By default, the primary or identity column is used as the qualifier. To override, pass a list of Field objects in the qualifiers argument.

using (var connection = new EDBConnection(connectionString))
{
    var people = GetPeople(10000);
    var updatedRows = connection.BulkUpdate<Person>(people,
        qualifiers: e => new { e.Name });
}

Use indexed columns from the target table as qualifiers to maximize performance.

Column Mappings

Add column mappings using the EDBBulkInsertMapItem class.

var mappings = new List<EDBBulkInsertMapItem>();

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

// Execute
using (var connection = new EDBConnection(connectionString))
{
    var people = GetPeople(10000);
    var updatedRows = connection.BulkUpdate(people,
        mappings: mappings);
}

Targeting a Table

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

using (var connection = new EDBConnection(connectionString))
{
    var people = GetPeople(10000);
    var updatedRows = connection.BulkUpdate("\"Person\"", people);
}

Async Method

An equivalent BulkUpdateAsync method is also available.

using (var connection = new EDBConnection(connectionString))
{
    var updatedRows = await connection.BulkUpdateAsync(people);
}