/// <summary> /// 创建 DELETE 命令 /// </summary> /// <param name="dbQuery">查询语义</param> /// <param name="token">解析上下文</param> /// <returns></returns> protected override RawCommand ResolveDeleteCommand <T>(IDbQueryableInfo_Delete dbQuery, ResolveToken token) { var context = (SqlServerDbContext)token.DbContext; ISqlBuilder builder = this.CreateSqlBuilder(token); var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo <T>(); builder.Append("DELETE t0 FROM "); builder.AppendMember(typeRuntime.TableName, !typeRuntime.IsTemporary); builder.Append(" t0 "); if (dbQuery.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 = dbQuery.Entity; builder.AppendNewLine(); builder.Append("WHERE "); foreach (var m in typeRuntime.KeyMembers) { var column = m.Column; var value = m.Invoke(entity); var seg = this.DbValue.GetSqlValue(value, token, column); builder.AppendMember("t0", m.Member.Name); builder.Append(" = "); builder.Append(seg); builder.Append(" AND "); } builder.Length -= 5; } else if (dbQuery.Query != null) { TableAlias aliases = this.PrepareTableAlias(dbQuery.Query, token); var cmd = new SqlServerMappingCommand(context, aliases, token) { HasMany = dbQuery.Query.HasMany }; ExpressionVisitorBase visitor = new SqlServerJoinExpressionVisitor(context, aliases, dbQuery.Query.Joins); visitor.Write(cmd.JoinFragment); visitor = new WhereExpressionVisitor(this, aliases, dbQuery.Query.Where); visitor.Write(cmd.WhereFragment); cmd.AddNavMembers(visitor.NavMembers); builder.Append(cmd.CommandText); } return(new RawCommand(builder.ToString(), builder.Token != null ? builder.Token.Parameters : null, System.Data.CommandType.Text)); }
/// <summary> /// 创建 DELETE 命令 /// </summary> /// <param name="dbQuery">查询语义</param> /// <param name="token">解析上下文</param> /// <returns></returns> protected override RawCommand ResolveDeleteCommand <T>(IDbQueryableInfo_Delete dbQuery, ResolveToken token) { ISqlBuilder builder = this.CreateSqlBuilder(token); var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo <T>(); builder.Append("DELETE FROM "); builder.AppendMember(typeRuntime.TableName, !typeRuntime.IsTemporary); builder.Append(" "); if (dbQuery.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 = dbQuery.Entity; builder.AppendNewLine(); builder.Append("WHERE "); foreach (var m in typeRuntime.KeyMembers) { var column = m.Column; var value = m.Invoke(entity); var seg = this.DbValue.GetSqlValue(value, token, column); builder.AppendMember(m.Member.Name); builder.Append(" = "); builder.Append(seg); builder.Append(" AND "); } builder.Length -= 5; } else if (dbQuery.Query != null) { // 解析查询用来确定是否需要嵌套 var cmd = this.ResolveSelectCommand(dbQuery.Query, 1, false, null) as MappingCommand; if (token != null && token.Extendsions == null) { token.Extendsions = new Dictionary <string, object>(); if (!token.Extendsions.ContainsKey("SQLiteDelete")) { token.Extendsions.Add("SQLiteDelete", null); } } if ((cmd.NavMembers != null && cmd.NavMembers.Count > 0) || dbQuery.Query.Joins.Count > 0) { // 最外层仅选择 RowID 列 var outQuery = dbQuery.Query; outQuery.Select = new DbExpression(DbExpressionType.Select, Expression.Constant("t0.RowId", typeof(string))); var iterator = outQuery; while (iterator.Subquery != null) { var subQuery = new SQLiteDbQueryableInfo_Select(iterator.Subquery); iterator.Subquery = subQuery; iterator = subQuery; } // 解析成 RowId IN 结构 cmd = (MappingCommand)this.ResolveSelectCommand(dbQuery.Query, 1, false, token); builder.Append("WHERE "); builder.AppendMember("RowID"); builder.Append(" IN("); builder.AppendNewLine(cmd.CommandText); builder.Append(')'); } else { TableAlias aliases = this.PrepareTableAlias(dbQuery.Query, token); ExpressionVisitorBase visitor = null; visitor = new JoinExpressionVisitor(this, aliases, dbQuery.Query.Joins); visitor.Write(builder); visitor = new WhereExpressionVisitor(this, null, dbQuery.Query.Where); visitor.Write(builder); } } builder.Append(';'); return(new RawCommand(builder.ToString(), builder.Token != null ? builder.Token.Parameters : null, System.Data.CommandType.Text)); }
/// <summary> /// 创建 DELETE 命令 /// </summary> /// <param name="dbQuery">查询语义</param> /// <param name="token">解析上下文</param> /// <returns></returns> protected abstract RawCommand ResolveDeleteCommand <T>(IDbQueryableInfo_Delete dbQuery, ResolveToken token);