Fix schema related methods in OracleProvider

Several issues were preventing AddColumn, DropColumn from working:

-Commands contained terminating semicolon
-Variable names in SQL text were prefixed with '@' instead of ':'
-Adding a column on Oracle uses the syntax "ADD <columnname>" instead of "ADD COLUMN <columnname>"

DoesTableExist and DoesColumnExist had problems when using the Schema attribute:

-The views USER_TABLES and USER_TAB_COLS only show objects owned by the current user
 Replaced with ALL_TABLES and ALL_TAB_COLS respectively

Linked SchemaTests into Oracle test project to verify fixes

Author: Cormac Brennan

src/ServiceStack.OrmLite.Oracle.Tests/ServiceStack.OrmLite.Oracle.Tests.csproj

@@ -292,6 +292,9 @@
     <Compile Include="..\..\tests\ServiceStack.OrmLite.Tests\RowVersionTests.cs">
       <Link>RowVersionTests.cs</Link>
     </Compile>
+    <Compile Include="..\..\tests\ServiceStack.OrmLite.Tests\SchemaTests.cs">
+      <Link>SchemaTests.cs</Link>
+    </Compile>
     <Compile Include="..\..\tests\ServiceStack.OrmLite.Tests\Shared\ApiUtilExtensions.cs">
       <Link>Shared\ApiUtilExtensions.cs</Link>
     </Compile>

src/ServiceStack.OrmLite.Oracle/OracleOrmLiteDialectProvider.cs

@@ -1192,11 +1192,37 @@ public override IDbDataParameter CreateParam()
             return _factory.CreateParameter();
         }
 
+        public override string ToAddColumnStatement(Type modelType, FieldDefinition fieldDef)
+        {
+            var command = base.ToAddColumnStatement(modelType, fieldDef);
+
+            command = RemoveTerminatingSemicolon(command);
+
+            return command.Replace("ADD COLUMN", "ADD");
+        }
+
+        private static string RemoveTerminatingSemicolon(string command)
+        {
+            command = command.Trim();
+
+            if (command[command.Length - 1] == ';') command = command.Substring(0, command.Length - 1);
+
+            return command;
+        }
+
+        protected override string ToDropColumnStatement(Type modelType, string columnName, IOrmLiteDialectProvider provider)
+        {
+            var command = base.ToDropColumnStatement(modelType, columnName, provider);
+
+            return RemoveTerminatingSemicolon(command);
+        }
+
         public override bool DoesTableExist(IDbCommand dbCmd, string tableName, string schema=null)
         {
             if (!WillQuote(tableName)) tableName = tableName.ToUpper();
 
-            var sql = "SELECT count(*) FROM USER_TABLES WHERE TABLE_NAME = {0}".SqlFmt(tableName);
+            tableName = RemoveSchemaName(tableName);
+            var sql = "SELECT count(*) FROM ALL_TABLES WHERE TABLE_NAME = {0}".SqlFmt(tableName);
 
             if (schema != null)
                 sql += " AND OWNER = {0}".SqlFmt(schema);
@@ -1207,17 +1233,25 @@ public override bool DoesTableExist(IDbCommand dbCmd, string tableName, string s
             return result > 0;
         }
 
+        private static string RemoveSchemaName(string tableName)
+        {
+            var indexOfPeriod = tableName.IndexOf(".", StringComparison.Ordinal);
+            return indexOfPeriod < 0 ? tableName : tableName.Substring(indexOfPeriod + 1);
+        }
+
         public override bool DoesColumnExist(IDbConnection db, string columnName, string tableName, string schema = null)
         {
             if (!WillQuote(tableName))
                 tableName = tableName.ToUpper();
 
-            var sql = "SELECT count(*) from user_tab_cols"
-                    + " WHERE table_name = @tableName"
-                    + "   AND column_name = @columnName";
+            columnName = columnName.ToUpper();
+            tableName = RemoveSchemaName(tableName);
+            var sql = "SELECT count(*) from all_tab_cols"
+                    + " WHERE table_name = :tableName"
+                    + "   AND upper(column_name) = :columnName";
 
             if (schema != null)
-                sql += " AND OWNER = @schema";
+                sql += " AND OWNER = :schema";
 
             var result = db.SqlScalar<long>(sql, new { tableName, columnName, schema });
 

src/ServiceStack.OrmLite/OrmLiteDialectProviderBase.cs

@@ -1544,12 +1544,17 @@ public virtual string ToRowCountStatement(string innerSql)
         public virtual void DropColumn(IDbConnection db, Type modelType, string columnName)
         {
             var provider = db.GetDialectProvider();
-            var command = $"ALTER TABLE {provider.GetQuotedTableName(modelType.GetModelDefinition().ModelName)} " +
-                          $"DROP COLUMN {provider.GetQuotedColumnName(columnName)};";
+            var command = ToDropColumnStatement(modelType, columnName, provider);
 
             db.ExecuteSql(command);
         }
 
+        protected virtual string ToDropColumnStatement(Type modelType, string columnName, IOrmLiteDialectProvider provider)
+        {
+            return $"ALTER TABLE {provider.GetQuotedTableName(modelType.GetModelDefinition().ModelName)} " +
+                   $"DROP COLUMN {provider.GetQuotedColumnName(columnName)};";
+        }
+
         //Async API's, should be overrided by Dialect Providers to use .ConfigureAwait(false)
         //Default impl below uses TaskAwaiter shim in async.cs