Net4x.DapperLibrary.StatementBuilder 1.9.9.1

DapperLibrary.StatementBuilder

A lightweight SQL statement builder used by the DapperLibraries to generate parameterized SQL for common operations (SELECT, CREATE TABLE, MERGE/UPSERT and WHERE clauses) from in-memory data sources such as DataTable and DbDataReader.

Goals

• Produce provider-agnostic, parameterized SQL statements.
• Support multiple input sources: DataTable, DbDataReader and in-memory definitions.
• Provide helpers for building merge/upsert commands, create-table statements and select/where clauses.
• Centralize parameter naming and extraction logic to keep calling code simple and safe.

Main components

• CreateStatementHelper / CreateStatementHelperInternal

  • Build CREATE TABLE statements from metadata (column names, types and sizes).
  • Used by higher-level helpers that ensure a table exists before saving data.

• ParameterBuilder, ParameterBuilderInternal, ParameterBuilder.*.cs

  • Create parameter lists and names for different input types (DataTable, DataReader).
  • Ensures consistent parameter prefixes and optional indexing depending on provider conventions.

• MergeCommandBuilder, MergeCommandBuilder.DataTable, MergeCommandBuilder.DataReader

  • Build MERGE or upsert-style statements tailored to the available provider and metadata.
  • Used by the merge/save utilities in DapperLibrary.MergeUtility and other save helpers.

• WhereBuilderInternal and OperatorUtility

  • Construct WHERE clauses and map operators (equality, range, LIKE, IN, etc.) to SQL snippets.
  • Used by read and delete helpers that require dynamic predicates.

• ColumnNamesExtractor and IColumnNamesExtractor

  • Extract column name lists from DataTable or DbDataReader inputs and normalize them for SQL generation.

• SelectDefinition and operators model

  • Small models that represent select clause definitions and supported operators used when generating queries.

Extension helpers

• StatementBuilderExtensions contains extension methods that wire the statement builder into the rest of the DapperLibraries codebase, providing convenient entry points for common scenarios.

Usage examples

• Build parameters for a DataTable row:

  var builder = new ParameterBuilder();
  var parameters = builder.BuildParametersFromDataTableRow(dataTable, rowIndex);
  // pass parameters to a generated SQL statement
  

• Generate a MERGE statement from a DataTable:

  var mergeBuilder = new MergeCommandBuilder();
  var mergeSql = mergeBuilder.BuildMergeFromDataTable(dataTable, primaryKeys);
  // Execute mergeSql with parameters against IDapperContext
  

• Create a table SQL from metadata:

  var createSql = CreateStatementHelper.CreateTableSql(tableName, columnsMetadata);
  

Compatibility and notes

• The library uses provider-agnostic abstractions but consumers should be aware of SQL dialect differences (particularly for MERGE statements). The generated SQL may be adapted by provider-specific code in the higher-level DapperLibrary projects.
• Parameter naming and indexing behavior can vary by provider; the ParameterBuilder supports common patterns and can be extended for custom provider rules.
• Project contains code targeting older .NET Framework versions and modern .NET. Use a compatible build/assembly for your runtime.

Extending

• Implement IColumnNamesExtractor when adding custom input types.
• Extend OperatorUtility and WhereBuilderInternal to add custom operators or provider-specific behaviors.
• Add provider-specific SQL emitters if your DB requires specialized MERGE or UPSERT syntax.

License / Contributing

See repository root for license and contribution guidelines.