Saxonite/Workspace/SaxoniteStandardDbas/Dbas/Data/SaxDbDataItem.cs

using Sarand.Net.Standard.Dbas.Data;
using Sarand.Net.Standard.Base.Core;
using Sarand.Net.Standard.Base.Dbas;
using System;
using System.Collections.Generic;
using System.Text;
using Sarand.Net.Standard.Base.Utils;

namespace Saxonite.Net.Standard.Dbas.Data
{
	//=======================================================================
	public abstract class SaxDbDataItem : DbDataItem
	{
		//-------------------------------------------------------------------
		// Definitions.
		/// <summary>
		/// Database information - object supplied by main application.
		/// <para>NB Application may have multiple databases with schema differences.</para>
		/// <para>Each instance of a DbDataItem must be database specific.</para>
		/// </summary>
		public class SlmDatabaseInfo : IDatabaseInfo
		{
			// Data members.
			private readonly List<DbDfnTable> tables;
			private static readonly String defaultSchemaName = "dbo";
			// Construction.
			public SlmDatabaseInfo(String databaseName, List<DbDfnTable> tables)
			{
				this.DatabaseName = databaseName;
				this.tables = tables;
			}
			// Properties.
			public String DatabaseName { get; }
			public String Context { get { return StringUtil.OnEmpty(DatabaseName, "UnknownDb"); } }
			// Database schema.
			public DbDfnTable GetTableDefinition(String schemaName, String tableName)
			{
				foreach (DbDfnTable table in tables.FindAll(item => item.Name.EqualsCI(tableName)))
				{
					if (StringUtil.OnEmpty(table.Schema, defaultSchemaName).EqualsCI(StringUtil.OnEmpty(schemaName, defaultSchemaName)))
						return table;
				}
				return null;
			}
			public bool TableExists(String schemaName, String tableName)
			{
				return GetTableDefinition(schemaName, tableName) != null;
			}
			public bool ColumnExists(String schemaName, String tableName, String columnName)
			{
				DbDfnTable table = GetTableDefinition(schemaName, tableName);
				if (table == null) return false;
				return table.HasColumnByName(columnName);
			}
			public List<DbDfnColumn> GetColumnsForTable(String schemaName, String tableName)
			{
				DbDfnTable table = GetTableDefinition(schemaName, tableName);
				if (table != null) return table.Columns;
				return new List<DbDfnColumn>();
			}
		}

		//-------------------------------------------------------------------
		// Construction.
		protected SaxDbDataItem(IDatabaseInfo dbInfo) : base(dbInfo)
		{
		}

		//-------------------------------------------------------------------

		//-------------------------------------------------------------------
	}
	//=======================================================================
}