/// <summary> /// 创建 DELETE 命令 /// </summary> /// <param name="tree">查询语义</param> /// <param name="context">解析SQL命令上下文</param> /// <returns></returns> protected override DbRawCommand TranslateDeleteCommand <T>(DbQueryDeleteTree tree, ITranslateContext context) { ISqlBuilder builder = this.CreateSqlBuilder(context); var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo <T>(); builder.Append("DELETE FROM "); builder.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); builder.Append(" t0 "); if (tree.Entity != null) { if (typeRuntime.KeyMembers == null || typeRuntime.KeyMembers.Count == 0) { throw new XFrameworkException("Delete<T>(T value) require entity must have key column."); } object entity = tree.Entity; builder.AppendNewLine(); builder.Append("WHERE "); foreach (FieldAccessorBase m in typeRuntime.KeyMembers) { var value = m.Invoke(entity); var sqlExpression = this.Constor.GetSqlValue(value, context, m.Column); builder.AppendMember("t0", m.Member, typeRuntime.Type); builder.Append(" = "); builder.Append(sqlExpression); builder.Append(" AND "); } builder.Length -= 5; } else if (tree.Select != null) { AliasGenerator ag = this.PrepareTableAlias(tree.Select, context.AliasPrefix); var cmd = new NpgDbSelectCommand(context, ag, DbExpressionType.Delete, tree.Select.SelectHasMany); if (tree.Select.Joins != null) { var visitor = new NpgJoinExpressionVisitor(ag, cmd.JoinFragment, DbExpressionType.Delete, cmd); visitor.Visit(tree.Select.Joins); } if (tree.Select.Wheres != null) { var visitor = new NpgWhereExpressionVisitor(ag, cmd.WhereFragment); visitor.Visit(tree.Select.Wheres); cmd.AddNavMembers(visitor.NavMembers); } builder.Append(cmd.CommandText); } builder.Append(';'); return(new DbRawCommand(builder.ToString(), builder.TranslateContext != null ? builder.TranslateContext.Parameters : null, System.Data.CommandType.Text)); }
/// <summary> /// 创建 UPDATE 命令 /// </summary> /// <param name="tree">查询语义</param> /// <param name="context">解析SQL命令上下文</param> /// <returns></returns> protected override DbRawCommand TranslateUpdateCommand <T>(DbQueryUpdateTree tree, ITranslateContext context) { ISqlBuilder builder = this.CreateSqlBuilder(context); var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo <T>(); builder.Append("UPDATE "); builder.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); builder.Append(" t0 SET"); builder.AppendNewLine(); if (tree.Entity != null) { object entity = tree.Entity; ISqlBuilder whereBuilder = this.CreateSqlBuilder(context); bool useKey = false; int length = 0; foreach (var item in typeRuntime.Members) { var m = item as FieldAccessorBase; if (m == null || !m.IsDbField) { continue; } if (m.Column != null && m.Column.IsIdentity) { goto LABEL; // Fix issue# 自增列同时又是主键 } builder.AppendMember(null, m.Member, typeRuntime.Type); builder.Append(" = "); LABEL: var value = m.Invoke(entity); var sqlExpression = this.Constor.GetSqlValueWidthDefault(value, context, m.Column); if (m.Column == null || !m.Column.IsIdentity) { builder.Append(sqlExpression); length = builder.Length; builder.Append(','); builder.AppendNewLine(); } if (m.Column != null && m.Column.IsKey) { useKey = true; whereBuilder.AppendMember(null, m.Member, typeRuntime.Type); whereBuilder.Append(" = "); whereBuilder.Append(sqlExpression); whereBuilder.Append(" AND "); } } if (!useKey) { throw new XFrameworkException("Update<T>(T value) require T must have key column."); } builder.Length = length; whereBuilder.Length -= 5; builder.AppendNewLine(); builder.Append("WHERE "); builder.Append(whereBuilder); } else if (tree.Expression != null) { AliasGenerator ag = this.PrepareTableAlias(tree.Select, context.AliasPrefix); DbExpressionVisitor visitor = null; visitor = new NpgUpdateExpressionVisitor(ag, builder); visitor.Visit(tree.Expression); var cmd = new NpgDbSelectCommand(context, ag, DbExpressionType.Update, tree.Select.SelectHasMany); if (tree.Select.Joins != null) { visitor = new NpgJoinExpressionVisitor(ag, cmd.JoinFragment, DbExpressionType.Update, cmd); visitor.Visit(tree.Select.Joins); } if (tree.Select.Wheres != null) { visitor = new NpgWhereExpressionVisitor(ag, cmd.WhereFragment); visitor.Visit(tree.Select.Wheres); cmd.AddNavMembers(visitor.NavMembers); } builder.Append(cmd.CommandText); } builder.Append(';'); return(new DbRawCommand(builder.ToString(), builder.TranslateContext != null ? builder.TranslateContext.Parameters : null, System.Data.CommandType.Text)); }