Exemple #1
0
        /// <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));
        }
Exemple #2
0
        /// <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));
        }