Adding missing code comments/documentation

src/Umbraco.Core/Persistence/SqlSyntax/ISqlSyntaxProvider.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using Umbraco.Core.Persistence.DatabaseAnnotations;
+using Umbraco.Core.Persistence.SqlSyntax.ModelDefinitions;
+
+namespace Umbraco.Core.Persistence.SqlSyntax
+{
+    /// <summary>
+    /// Defines an SqlSyntaxProvider
+    /// </summary>
+    public interface ISqlSyntaxProvider
+    {
+        string GetQuotedTableName(string tableName);
+        string GetQuotedColumnName(string columnName);
+        string GetQuotedName(string name);
+        bool DoesTableExist(Database db, string tableName);
+        string ToCreateTableStatement(TableDefinition tableDefinition);
+        List<string> ToCreateForeignKeyStatements(TableDefinition tableDefinition);
+        List<string> ToCreateIndexStatements(TableDefinition tableDefinition);
+        DbType GetColumnDbType(Type valueType);
+        string GetIndexType(IndexTypes indexTypes);
+        string GetColumnDefinition(ColumnDefinition column, string tableName);
+        string GetPrimaryKeyStatement(ColumnDefinition column, string tableName);
+        string ToCreatePrimaryKeyStatement(TableDefinition table);
+        string GetSpecialDbType(SpecialDbTypes dbTypes);
+        string GetConstraintDefinition(ColumnDefinition column, string tableName);
+    }
+}