RepoDb.Vertica 0.0.1-alpha1

RepoDb.Vertica — RepoDB for Vertica

The Vertica provider for RepoDB — a fast, lightweight .NET ORM that lets you use raw SQL and fluent operations side by side on the same connection. Built on top of RepoDb and Vertica.Data.VerticaClient.

Important Pages

• GitHub Home — core library and source code.
• Website — full documentation, API reference, and blog.

Community

• GitHub Issues — bug reports and feature requests.
• Microsoft Teams — live Q&A.
• GitHub Discussions — ask questions and share ideas.
• X / Twitter — news and updates.

Dependencies

• Vertica.Data.VerticaClient — the Vertica ADO.NET data provider.
• RepoDb — the RepoDB core library.

Known limitations

• Targets Vertica 3.0 and later. Identity-column detection relies on RDB$RELATION_FIELDS.RDB$IDENTITY_TYPE, which does not exist on Vertica 2.5 and earlier; tables using the pre-3.0 trigger + generator pattern for auto-increment will not be detected as identity columns.
• InsertAll batches real multi-row INSERT INTO t (...) VALUES (...), (...), ... statements (IDbSetting.IsInsertAllBatchable = true) - a single statement, not multiple ;-separated ones, so it doesn't hit Vertica's compound-statement restriction. This matters: Vertica creates a new storage container (ROS) per statement, regardless of whether inserts share a transaction/commit, so one-row-at-a-time inserts exhaust the per-projection ROS container limit ("Too many ROS containers exist") on any sizeable InsertAll. A generated IDENTITY value for a batch is read back with a single LAST_INSERT_ID() query after the batch, then assigned to each row by computed offset - this assumes Vertica generates IDENTITY values contiguously and in input row order within one multi-row INSERT, which is unverified against a real (especially multi-node) cluster. MergeAll always executes one statement per row regardless (see below) - Vertica's ADO.NET provider does not support executing multiple separate statements in a single round-trip, unlike SQL Server/MySQL/PostgreSql.
• Vertica has neither a native single-statement upsert nor a usable MERGE for this purpose: it has no UPDATE OR INSERT ... MATCHING statement, and its ANSI MERGE fails outright (error 4711, "Sequence or IDENTITY/AUTO_INCREMENT column in merge query is not supported") against any table carrying an IDENTITY column, whether or not that column is referenced. Nor can a compound (stmt1; stmt2) statement stand in for it: VerticaCommand refuses to execute one at all once it carries a parameter, on every Execute* call (it always prepares first internally), not just when .Prepare() is called explicitly. Merge/MergeAll therefore set IsUseUpsert = true, routing through RepoDb.Core's Exists + Update/Insert fallback - genuinely separate, single-statement round-trips - instead of a single atomic statement.
• Vertica has no RETURNING clause on any DML. A generated IDENTITY value is instead read back via a separate SELECT LAST_INSERT_ID() query (Vertica's session-scoped equivalent of SCOPE_IDENTITY(), valid only for IDENTITY columns, not named sequences) - see VerticaDbHelper.GetScopeIdentity, called automatically by RepoDb.Core's Insert/InsertAll as a fallback whenever the insert's own ExecuteScalar() doesn't yield a value.
• Vertica's driver materializes a TIME column's value as a full DateTime combined with the current date at the time of the read, not a fixed placeholder date - so a value written and read back would otherwise never compare equal to itself. There is no accessor that returns a bare TimeSpan for a TIME column. Apply VerticaTimeToDateTimePropertyHandler to any DateTime-typed property mapped to a TIME column to re-base it onto DateTime's default date; it is opt-in (not auto-registered) since PropertyHandlerMapper registrations by CLR type are global and would otherwise also affect DATE/TIMESTAMP columns.
  • This only fixes typed-entity queries (Query<TEntity>, Merge<TEntity>, etc.), since PropertyHandlerMapper is keyed by (EntityType, PropertyInfo) - an actual CLR property to attach to. Dynamic/ExpandoObject reads (*ViaTableName operations, a dynamic Query/ExecuteQuery) go through RepoDb.Core's dictionary-binding compiler, which reads the raw driver value directly with no property-handler hook at all. Fixing that path would require wrapping Vertica's (sealed, so un-subclassable) VerticaConnection/VerticaCommand/VerticaDataReader behind a from-scratch delegating DbConnection/DbCommand/DbDataReader triplet - not implemented. A TIME column read back through a dynamic path will show today's date instead of a placeholder.

License

Apache-2.0 — Copyright © 2020 Michael Camara Pendon

Installation

Install-Package RepoDb.Vertica

Or visit the installation page for more options.

Get Started

Initialize the bootstrapper once at application startup:

GlobalConfiguration
    .Setup()
    .UseVertica();

Then use any RepoDB operation directly on your VerticaConnection:

Query

using (var connection = new VerticaConnection(ConnectionString))
{
	var customer = connection.Query<Customer>(c => c.Id == 10045);
}

Insert

var customer = new Customer
{
	FirstName = "John",
	LastName = "Doe",
	IsActive = true
};
using (var connection = new VerticaConnection(ConnectionString))
{
	var id = connection.Insert<Customer>(customer);
}

Update

using (var connection = new VerticaConnection(ConnectionString))
{
	var customer = connection.Query<Customer>(10045);
	customer.FirstName = "John";
	customer.LastUpdatedUtc = DateTime.UtcNow;
	var affectedRows = connection.Update<Customer>(customer);
}

Delete

using (var connection = new VerticaConnection(ConnectionString))
{
	var customer = connection.Query<Customer>(10045);
	var deletedCount = connection.Delete<Customer>(customer);
}

ExecuteQuery

using (var connection = new VerticaConnection(ConnectionString))
{
	var customer = connection.ExecuteQuery<Customer>("SELECT * FROM \"Customer\" WHERE (\"Id\" = @Id)", new { Id = 10045 }).FirstOrDefault();
}

ExecuteNonQuery

using (var connection = new VerticaConnection(ConnectionString))
{
	var affectedRows = connection.ExecuteNonQuery("UPDATE \"Customer\" SET \"FirstName\" = @FirstName WHERE (\"Id\" = @Id)", new { FirstName = "John", Id = 10045 });
}

ExecuteScalar

using (var connection = new VerticaConnection(ConnectionString))
{
	var count = connection.ExecuteScalar<int>("SELECT COUNT(*) FROM \"Customer\"");
}

Visit the get-started page for the full Vertica guide.

License

Apache-2.0 — Copyright © 2020 Michael Camara Pendon