Codeer.LowCode.Blazor.DbAccess

Multi-database access layer for Codeer.LowCode.Blazor server applications.

Provides the standard IDbAccessor implementation (DbAccessor) used by the server side of a Codeer.LowCode.Blazor application. It supports SQL Server / PostgreSQL / Oracle / SQLite / MySQL with a single API, using Dapper for parameter binding and a common row-materialization path.

• NuGet: Codeer.LowCode.Blazor.DbAccess
• License: MIT (this project). See the note below about bundled database providers.

Usage

Reference the package from your server project and register DbAccessor as the IDbAccessor (exactly as the application templates do):

usingCodeer.LowCode.Blazor.DbAccess;IDbAccessoraccessor=newDbAccessor(dataSources);

Every member of DbAccessor is virtual, so you can subclass it to insert logging, retries, or provider-specific value binding without forking the code:

publicclassMyDbAccessor:DbAccessor{publicMyDbAccessor(DataSource[]dataSources):base(dataSources){}publicoverrideasyncTask<List<IDictionary<string,object>>>QueryAsync(stringdataSourceName,stringquery,Dictionary<string,ParamAndRawDbTypeName>args){// ... custom logging / retry ...returnawaitbase.QueryAsync(dataSourceName,query,args);}}

If you prefer not to take a dependency on this package, copy the source from this repository into your own project and modify it as needed.

SQL debug logging

Since the package source cannot be stepped into while debugging, DbAccessor provides a debug log mode instead. Assign a sink to the static DbAccessor.SqlLog property and every execution (QueryAsync / ExecuteAsync / InsertAsync / ExecuteSqlCommandAsync) dumps the SQL and its parameters — including output parameter values after execution. It is null by default (disabled, no overhead).

// e.g. in Program.cs, for development onlyDbAccessor.SqlLog=Console.WriteLine;// or route to your loggerDbAccessor.SqlLog= message =>logger.LogDebug(message);

Example output:

[SQL] Query (Main)
--------------------------------------------------
SELECT * FROM t WHERE id = @id
--------------------------------------------------
id = 123 (Int32)
[SQL] ExecuteSqlCommand NonQuery (Main)
--------------------------------------------------
BEGIN PROC_PARAM_TEST(:num_in, :num_out); END;
--------------------------------------------------
num_in = 111 (Decimal) (Input, Decimal)
num_out = null (Output, Decimal)
[SQL] ExecuteSqlCommand result (Main)
ReturnValue = -1 (Int32)
num_out = 1110 (OracleDecimal)

Note: parameter values may contain sensitive data — enable this only in development environments.

Database provider licenses

This package declares (but does not redistribute) the following database providers. Each is restored by NuGet on the consumer side:

Provider	License
Dapper	Apache-2.0
Microsoft.Data.SqlClient	MIT
Microsoft.Data.Sqlite	MIT
Npgsql	PostgreSQL License
MySqlConnector	MIT
Oracle.ManagedDataAccess.Core	Oracle Free Use Terms and Conditions (FUTC) — free to use, but not open source
Microsoft.EntityFrameworkCore(.Relational)	MIT

All are free for commercial use. Only the Oracle provider is under a proprietary (though free) license rather than an OSI-approved open-source license; review the Oracle FUTC if that matters to you.