// 解译 SELECT 语句 private DbRawCommand TranslateSelectCommandImpl(DbQuerySelectTree tree, int indent, bool isOutermost, ITranslateContext context) { // 说明: // 1.OFFSET 前必须要有 'ORDER BY',即 'Skip' 子句前必须使用 'OrderBy' 子句 // 2.在有聚合函数的<MAX,MIN...>情况下,如果有 'Distinct' 'GroupBy' 'Skip' 'Take' 子句,则需要使用嵌套查询 // 3.'Any' 子句将翻译成 IF EXISTS... // 4.分组再分页时需要使用嵌套查询,此时子查询不需要 'OrderBy' 子句,但最外层则需要 // 5.'Skip' 'Take' 子句视为语义结束符,在其之后的子句将使用嵌套查询 // 6.导航属性中有 1:n 关系的,需要使用嵌套查询,否则分页查询会有问题 // 8.如果只有 Skip 没有 Take,则使用 Row_Number() Over()分页语法,其它使用 LIMIT ## OFFSET 语法 // 导航属性中有1:n关系,只统计主表 // 例:AccountList = a.Client.AccountList, var subquery = tree.Subquery as DbQuerySelectTree; if (tree.SelectHasMany && subquery != null && subquery.Aggregate != null) { tree = subquery; } var srcDbExpressionType = context.CurrentExpressionType; var srcIsOutmost = context.CurrentIsOutermost; if (srcDbExpressionType == null) { context.CurrentExpressionType = DbExpressionType.Select; } if (srcIsOutmost == null || !isOutermost) { context.CurrentIsOutermost = isOutermost; } bool useAggregate = tree.Aggregate != null; // 没有聚合函数或者使用 'Skip' 子句,则解析OrderBy // 导航属性如果使用嵌套,除非有 TOP 或者 OFFSET 子句,否则不能用ORDER BY // 第一层的表别名 string alias = context != null && !string.IsNullOrEmpty(context.AliasPrefix) ? (context.AliasPrefix + "0") : "t0"; bool useSubquery = tree.HasDistinct || tree.GroupBy != null || tree.Skip > 0 || tree.Take > 0; bool useOrderBy = (!useAggregate || tree.Skip > 0) && !tree.HasAny && (!tree.SelectHasMany || (tree.Skip > 0 || tree.Take > 0)); AliasGenerator ag = this.PrepareTableAlias(tree, context != null ? context.AliasPrefix : null); var result = new DbSelectCommand(context, ag, tree.SelectHasMany); ISqlBuilder jf = result.JoinFragment; ISqlBuilder wf = result.WhereFragment; ISqlBuilder sf = null; jf.Indent = indent; #region 嵌套查询 if (useAggregate && useSubquery) { // SELECT jf.Append("SELECT "); jf.AppendNewLine(); // SELECT COUNT(1) var visitor = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, alias); visitor.Visit(tree.Aggregate); result.AddNavMembers(visitor.NavMembers); // SELECT COUNT(1) FROM jf.AppendNewLine(); jf.Append("FROM ( "); indent += 1; jf.Indent = indent; context.CurrentIsOutermost = false; } #endregion #region 择子句 // SELECT 子句 if (jf.Indent > 0) { jf.AppendNewLine(); } jf.Append("SELECT "); if (tree.HasAny) { jf.Append("CASE WHEN COUNT(1) = 1 THEN 1 ELSE 0 END FROM ("); indent += 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append("SELECT 1 "); } if (useAggregate && !useSubquery) { // 如果有聚合函数,并且不是嵌套的话,则直接使用SELECT <MAX,MIN...>,不需要解析选择的字段 jf.AppendNewLine(); var visitor_ = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, null); visitor_.Visit(tree.Aggregate); result.AddNavMembers(visitor_.NavMembers); } else { // DISTINCT 子句 if (tree.HasDistinct) { jf.Append("DISTINCT "); } #region 择字段 if (!tree.HasAny) { // SELECT 范围 ColumnExpressionVisitor visitor = null; if (tree.Skip > 0 && tree.Take == 0) { sf = this.CreateSqlBuilder(context); sf.Indent = jf.Indent + 1; visitor = new ColumnExpressionVisitor(ag, sf, tree); visitor.Visit(tree.Select); } else { visitor = new ColumnExpressionVisitor(ag, jf, tree); visitor.Visit(tree.Select); } result.SelectedColumns = visitor.SelectedColumns; result.SelectedColumnText = visitor.SelectedColumnText; result.SelectedNavs = visitor.SelectedNavDescriptors; result.AddNavMembers(visitor.NavMembers); if (sf != null) { // 第一层嵌套 int index = 0; jf.AppendNewLine(); foreach (var column in result.SelectedColumns) { jf.AppendMember(alias, column.Name); jf.AppendAs(column.NewName); index += 1; if (index < result.SelectedColumns.Count) { jf.Append(','); jf.AppendNewLine(); } } jf.AppendNewLine(); jf.Append("FROM("); // 第二层嵌套 indent += 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append("SELECT"); jf.Append(sf); jf.Append(','); jf.AppendNewLine(); if (tree.OrderBys == null || tree.OrderBys.Count == 0) { throw new XFrameworkException("The method 'OrderBy' must be called before 'Skip'."); } jf.Append("ROW_NUMBER() OVER("); var visitor3 = new OrderByExpressionVisitor(ag, jf, tree.GroupBy, null); visitor3.Visit(tree.OrderBys, false); result.AddNavMembers(visitor3.NavMembers); jf.Append(") Row_Number0"); } } #endregion } #endregion #region 顺序解析 // FROM 子句 jf.AppendNewLine(); jf.Append("FROM "); if (tree.Subquery != null) { // 子查询 jf.Append("("); var cmd = this.TranslateSelectCommandImpl(tree.Subquery, indent + 1, false, context); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else if (tree.FromSql != null) { if (tree.FromSql.DbContext == null) { tree.FromSql.DbContext = context.DbContext; } DbRawSql rawSql = tree.FromSql; // 解析参数 object[] args = null; if (rawSql.Parameters != null) { args = rawSql.Parameters.Select(x => this.Constor.GetSqlValue(x, context)).ToArray(); } string sql = rawSql.CommandText; if (args != null && args.Length > 0) { sql = string.Format(sql, args); } // 子查询 jf.Append('('); var cmd = new DbRawCommand(sql, context.Parameters, CommandType.Text); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else { var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo(tree.From); jf.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); jf.Append(' '); jf.Append(alias); jf.Append(' '); } // LEFT<INNER> JOIN 子句 if (tree.Joins != null) { var visitor = new JoinExpressionVisitor(ag, jf); visitor.Visit(tree.Joins); } wf.Indent = jf.Indent; // WHERE 子句 if (tree.Wheres != null) { var visitor = new WhereExpressionVisitor(ag, wf); visitor.Visit(tree.Wheres); result.AddNavMembers(visitor.NavMembers); } // GROUP BY 子句 if (tree.GroupBy != null) { var visitor = new GroupByExpressionVisitor(ag, wf); visitor.Visit(tree.GroupBy); result.AddNavMembers(visitor.NavMembers); } // HAVING 子句 if (tree.Havings != null) { var visitor = new HavingExpressionVisitor(ag, wf, tree.GroupBy); visitor.Visit(tree.Havings); result.AddNavMembers(visitor.NavMembers); } // ORDER 子句 if (tree.OrderBys != null && tree.OrderBys.Count > 0 && useOrderBy)// && !groupByPaging) { var visitor = new OrderByExpressionVisitor(ag, wf, tree.GroupBy, null); visitor.Visit(tree.OrderBys); result.AddNavMembers(visitor.NavMembers); } #endregion #region 分页查询 // LIMIT 子句可以被用于强制 SELECT 语句返回指定的记录数。 // LIMIT 接受一个或两个数字参数。参数必须是一个整数常量。如果给定两个参数,第一个参数指定第一个返回记录行的偏移量,第二个参数指定返回记录行的最大数目。 // 初始记录行的偏移量是 0(而不是 1): 为了与 PostgreSQL 兼容,MySQL 也支持句法: LIMIT # OFFSET #。 // Limit n,-1 语法不支持,使用ROW_Number()语法代替 if (tree.Take > 0) { wf.AppendNewLine().AppendFormat("LIMIT {0}", this.Constor.GetSqlValue(tree.Take, context)); wf.AppendFormat(" OFFSET {0}", this.Constor.GetSqlValue(tree.Skip, context)); } #endregion #region 嵌套查询 if (useAggregate && useSubquery) { result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); } #endregion #region 嵌套导航 // TODO Include 从表,没分页,OrderBy 报错 //if (tree.HasMany && subquery != null && subquery.OrderBys.Count > 0 && subquery.Aggregate == null && !(subquery.Skip > 0 || subquery.Take > 0)) if (tree.SelectHasMany && subquery.Aggregate == null && subquery != null && subquery.OrderBys != null && subquery.OrderBys.Count > 0 && !(subquery.Skip > 0 || subquery.Take > 0)) { result.CombineFragments(); var visitor = new OrderByExpressionVisitor(ag, jf, null, null); visitor.Visit(subquery.OrderBys); } #endregion #region 并集查询 // UNION 子句 if (tree.Unions != null && tree.Unions.Count > 0) { result.CombineFragments(); for (int index = 0; index < tree.Unions.Count; index++) { jf.AppendNewLine(); jf.Append("UNION ALL"); if (indent == 0) { jf.AppendNewLine(); } DbRawCommand cmd = this.TranslateSelectCommandImpl(tree.Unions[index], indent, isOutermost, context); jf.Append(cmd.CommandText); } } #endregion #region 分页查询 if (sf != null) { // 合并 WHERE result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.AppendNewLine(); jf.Append("WHERE "); if (tree.Skip > 0) { jf.AppendMember(alias, "Row_Number0"); jf.Append(" > "); jf.Append(this.Constor.GetSqlValue(tree.Skip, context)); } } #endregion #region Any 子句 // 'Any' 子句 if (tree.HasAny) { // 产生 WHERE 子句 result.CombineFragments(); // 如果没有分页,则显式指定只查一笔记录 if (tree.Take == 0 && tree.Skip == 0) { jf.AppendNewLine(); jf.Append("LIMIT 0,1"); } indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); } #endregion #region 还原状态 context.CurrentExpressionType = srcDbExpressionType; context.CurrentIsOutermost = srcIsOutmost; #endregion return(result); }
/// <summary> /// 解析 SQL 命令 /// <para> /// 返回的已经解析语义中执行批次用 null 分开 /// </para> /// </summary> /// <param name="dbQueryables">查询语句</param> /// <returns></returns> public override List <DbRawCommand> Translate(List <object> dbQueryables) { bool haveBegin = false; ITranslateContext context = null; var sqlList = new List <DbRawCommand>(); for (int i = 0; i < dbQueryables.Count; i++) { object obj = dbQueryables[i]; if (obj == null) { continue; } if (obj is IDbQueryable) { DbQueryable dbQuery = (DbQueryable)obj; dbQuery.Parameterized = true; if (context == null) { context = this.CreateTranslateContext(dbQuery.DbContext); } if (context.Parameters == null) { context.Parameters = new List <IDbDataParameter>(8); } var cmd = dbQuery.Translate(0, true, context); if (cmd is DbSelectCommand) { // 查询单独执行 if (sqlList.Count > 0 && (i - 1) >= 0 && sqlList[sqlList.Count - 1] != null) { sqlList.Add(null); } sqlList.Add(cmd); sqlList.Add(null); context = this.CreateTranslateContext(dbQuery.DbContext); context.Parameters = new List <IDbDataParameter>(8); } else { // 增删改 if (!haveBegin) { sqlList.Add(new DbRawCommand("BEGIN")); haveBegin = true; } sqlList.Add(cmd); if (cmd.Parameters != null && cmd.Parameters.Count > 1000) { // 1000个参数,就要重新分批 if (haveBegin) { sqlList.Add(new DbRawCommand("END;")); haveBegin = false; sqlList.Add(null); } context = this.CreateTranslateContext(dbQuery.DbContext); context.Parameters = new List <IDbDataParameter>(8); } if (i + 1 < dbQueryables.Count) { // 检查下一条是否是选择语句 bool isQuery = false; if (dbQueryables[i + 1] is IDbQueryable) { var tree = ((DbQueryable)dbQueryables[i + 1]).Parse(); isQuery = tree is DbQuerySelectTree; } else if ((dbQueryables[i + 1] is string)) { string sql = dbQueryables[i + 1].ToString(); string method = string.Empty; if (sql.Length > 6) { method = sql.Substring(0, 6).Trim().ToUpper(); } isQuery = method == "SELECT"; } else if (dbQueryables[i + 1] is DbRawSql) { string sql = ((DbRawSql)dbQueryables[i + 1]).CommandText; string method = string.Empty; if (sql.Length > 6) { method = sql.Substring(0, 6).Trim().ToUpper(); } isQuery = method == "SELECT"; } // 如果下一条是SELECT 语句,则需要结束当前语句块 if (isQuery) { if (haveBegin) { sqlList.Add(new DbRawCommand("END;")); haveBegin = false; sqlList.Add(null); } context = this.CreateTranslateContext(dbQuery.DbContext); context.Parameters = new List <IDbDataParameter>(8); } } } } else if (obj is DbRawSql || obj is string) { string sql = string.Empty; if (obj is string) { sql = obj.ToString(); } else { DbRawSql rawSql = (DbRawSql)obj; // 解析参数 object[] args = null; if (rawSql.Parameters != null) { args = rawSql.Parameters.Select(x => this.Constor.GetSqlValue(x, context)).ToArray(); } sql = rawSql.CommandText; if (args != null && args.Length > 0) { sql = string.Format(sql, args); } } string methodName = string.Empty; if (sql.Length > 6) { methodName = sql.Substring(0, 6).Trim().ToUpper(); } if (methodName == "SELECT") { if (sqlList.Count > 0 && (i - 1) >= 0 && sqlList[sqlList.Count - 1] != null) { sqlList.Add(null); } } var cmd = new DbRawCommand(sql, context.Parameters, CommandType.Text); sqlList.Add(cmd); if (methodName == "SELECT") { sqlList.Add(cmd); sqlList.Add(null); context = this.CreateTranslateContext(obj is DbRawSql ? ((DbRawSql)obj).DbContext : null); context.Parameters = new List <IDbDataParameter>(8); } else if (cmd.Parameters != null && cmd.Parameters.Count > 1000) { // 1000个参数,就要重新分批 if (haveBegin) { sqlList.Add(new DbRawCommand("END;")); sqlList.Add(null); haveBegin = false; } context = this.CreateTranslateContext(obj is DbRawSql ? ((DbRawSql)obj).DbContext : null); context.Parameters = new List <IDbDataParameter>(8); } } else { if (!haveBegin) { sqlList.Add(new DbRawCommand("BEGIN")); haveBegin = true; } // 解析批量插入操作 List <IDbQueryable> bulkList = obj as List <IDbQueryable>; if (bulkList != null && bulkList.Count > 0) { this.TranslateBulk(sqlList, bulkList); } } if (haveBegin && i == dbQueryables.Count - 1) { sqlList.Add(new DbRawCommand("END;")); } } return(sqlList); }
/// <summary> /// 解析 SELECT 命令 /// </summary> /// <param name="tree">查询语义</param> /// <param name="indent">缩进</param> /// <param name="isOutermost">是否是最外层查询</param> /// <param name="context">解析SQL命令上下文</param> /// <returns></returns> protected override DbRawCommand TranslateSelectCommand(DbQuerySelectTree tree, int indent, bool isOutermost, ITranslateContext context) { // 说明: // 1.OFFSET 前必须要有 'ORDER BY',即 'Skip' 子句前必须使用 'OrderBy' 子句 // 2.在有聚合函数的<MAX,MIN...>情况下,如果有 'Distinct' 'GroupBy' 'Skip' 'Take' 子句,则需要使用嵌套查询 // 3.'Any' 子句将翻译成 IF EXISTS... // 4.分组再分页时需要使用嵌套查询,此时子查询不需要 'OrderBy' 子句,但最外层则需要 // 5.'Skip' 'Take' 子句视为语义结束符,在其之后的子句将使用嵌套查询 // 6.导航属性中有 1:n 关系的,需要使用嵌套查询,否则分页查询会有问题 // 8.如果有分页,则使用嵌套 // 9.如果有分页还有OrderBy,则使用嵌套的嵌套 // 导航属性中有1:n关系,只统计主表 // 例:AccountList = a.Client.AccountList, var subquery = tree.Subquery as DbQuerySelectTree; if (tree.SelectHasMany && subquery != null && subquery.Aggregate != null) { tree = subquery; } var srcDbExpressionType = context.CurrentExpressionType; var srcIsOutmost = context.CurrentIsOutermost; if (srcDbExpressionType == null) { context.CurrentExpressionType = DbExpressionType.Select; } if (srcIsOutmost == null || !isOutermost) { context.CurrentIsOutermost = isOutermost; } bool useAggregate = tree.Aggregate != null; // 没有聚合函数或者使用 'Skip' 子句,则解析OrderBy // 导航属性如果使用嵌套,除非有 TOP 或者 OFFSET 子句,否则不能用ORDER BY // 第一层的表别名 string alias = context != null && !string.IsNullOrEmpty(context.AliasPrefix) ? (context.AliasPrefix + "0") : "t0"; bool useSubquery = tree.HasDistinct || tree.GroupBy != null || tree.Skip > 0 || tree.Take > 0; bool useOrderBy = (!useAggregate || tree.Skip > 0) && !tree.HasAny && (!tree.SelectHasMany || (tree.Skip > 0 || tree.Take > 0)); AliasGenerator ag = this.PrepareTableAlias(tree, context != null ? context.AliasPrefix : null); var result = new DbSelectCommand(context, ag, tree.SelectHasMany); ISqlBuilder jf = result.JoinFragment; ISqlBuilder wf = result.WhereFragment; (jf as OracleSqlBuilder).UseQuote = isOutermost; jf.Indent = indent; #region 嵌套查询 if (useAggregate && useSubquery) { // SELECT jf.Append("SELECT "); jf.AppendNewLine(); // SELECT COUNT(1) var visitor = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, alias); visitor.Visit(tree.Aggregate); result.AddNavMembers(visitor.NavMembers); // SELECT COUNT(1) FROM jf.AppendNewLine(); jf.Append("FROM ( "); indent += 1; jf.Indent = indent; (jf as OracleSqlBuilder).UseQuote = false; context.CurrentIsOutermost = false; } #endregion #region 择子句 // SELECT 子句 if (jf.Indent > 0) { jf.AppendNewLine(); } jf.Append("SELECT "); if (tree.HasAny) { jf.Append("CASE WHEN COUNT(1) = 1 THEN 1 ELSE 0 END FROM ("); indent += 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append("SELECT 1 "); } if (useAggregate && !useSubquery) { // 如果有聚合函数,并且不是嵌套的话,则直接使用SELECT <MAX,MIN...>,不需要解析选择的字段 jf.AppendNewLine(); var visitor = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, null); visitor.Visit(tree.Aggregate); result.AddNavMembers(visitor.NavMembers); } else { // DISTINCT 子句 if (tree.HasDistinct) { jf.Append("DISTINCT "); } #region 择字段 if (!tree.HasAny) { // SELECT 范围 ISqlBuilder sf = this.CreateSqlBuilder(context); sf.Indent = jf.Indent + ((tree.Skip > 0 || tree.Take > 0) ? 2 : 0); (sf as OracleSqlBuilder).UseQuote = (tree.Skip > 0 || tree.Take > 0) ? false : (jf as OracleSqlBuilder).UseQuote; var visitor = new OracleColumnExpressionVisitor(ag, sf, tree); visitor.Visit(tree.Select); result.SelectedColumns = visitor.SelectedColumns; result.SelectedColumnText = visitor.SelectedColumnText; result.SelectedNavs = visitor.SelectedNavDescriptors; result.AddNavMembers(visitor.NavMembers); // 分页,产生两层嵌套 if (tree.Skip > 0 || tree.Take > 0) { // 第一层嵌套 int index = 0; jf.AppendNewLine(); foreach (var column in result.SelectedColumns) { jf.AppendMember(alias, column.Name); jf.AppendAs(column.NewName); index += 1; if (index < result.SelectedColumns.Count) { jf.Append(','); jf.AppendNewLine(); } } jf.AppendNewLine(); jf.Append("FROM("); // 第二层嵌套 indent += 1; isOutermost = false; jf.Indent = indent; (jf as OracleSqlBuilder).UseQuote = isOutermost; jf.AppendNewLine(); jf.Append("SELECT"); jf.AppendNewLine(); foreach (var column in result.SelectedColumns) { jf.AppendMember(alias, column.NewName); jf.AppendAs(column.NewName); jf.Append(','); jf.AppendNewLine(); } jf.Append("ROWNUM"); jf.AppendAs("Row_Number0"); jf.AppendNewLine(); jf.Append("FROM("); // 第三层嵌套 indent += 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append("SELECT"); } jf.Append(sf); } #endregion } #endregion #region 顺序解析 // FROM 子句 jf.AppendNewLine(); jf.Append("FROM "); if (tree.Subquery != null) { // 子查询 jf.Append('('); DbRawCommand cmd = this.TranslateSelectCommand(tree.Subquery, indent + 1, false, context); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else if (tree.FromSql != null) { if (tree.FromSql.DbContext == null) { tree.FromSql.DbContext = context.DbContext; } DbRawSql rawSql = tree.FromSql; // 解析参数 object[] args = null; if (rawSql.Parameters != null) { args = rawSql.Parameters.Select(x => this.Constor.GetSqlValue(x, context)).ToArray(); } string sql = rawSql.CommandText; if (args != null && args.Length > 0) { sql = string.Format(sql, args); } // 子查询 jf.Append('('); var cmd = new DbRawCommand(sql, context.Parameters, CommandType.Text); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else { var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo(tree.From); jf.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); jf.Append(' '); jf.Append(alias); jf.Append(' '); } // LEFT<INNER> JOIN 子句 if (tree.Joins != null) { var visitor = new JoinExpressionVisitor(ag, jf); visitor.Visit(tree.Joins); } wf.Indent = jf.Indent; // WHERE 子句 if (tree.Wheres != null) { var visitor = new WhereExpressionVisitor(ag, wf); visitor.Visit(tree.Wheres); result.AddNavMembers(visitor.NavMembers); } // GROUP BY 子句 if (tree.GroupBy != null) { var visitor = new GroupByExpressionVisitor(ag, wf); visitor.Visit(tree.GroupBy); result.AddNavMembers(visitor.NavMembers); } // HAVING 子句 if (tree.Havings != null) { var visitor = new HavingExpressionVisitor(ag, wf, tree.GroupBy); visitor.Visit(tree.Havings); result.AddNavMembers(visitor.NavMembers); } // ORDER 子句 if (tree.OrderBys != null && tree.OrderBys.Count > 0 && useOrderBy) { var visitor = new OrderByExpressionVisitor(ag, wf, tree.GroupBy, null); visitor.Visit(tree.OrderBys); result.AddNavMembers(visitor.NavMembers); } #endregion #region 嵌套查询 if (useAggregate && useSubquery) { result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); } #endregion #region 嵌套导航 // TODO Include 从表,没分页,OrderBy 报错 if (tree.SelectHasMany && subquery.Aggregate == null && subquery != null && subquery.OrderBys != null && subquery.OrderBys.Count > 0 && !(subquery.Skip > 0 || subquery.Take > 0)) { // OrderBy("a.CloudServer.CloudServerName"); result.CombineFragments(); var visitor = new OrderByExpressionVisitor(ag, jf, null, null); visitor.Visit(subquery.OrderBys); } #endregion #region 并集查询 // UNION 子句 if (tree.Unions != null && tree.Unions.Count > 0) { result.CombineFragments(); for (int index = 0; index < tree.Unions.Count; index++) { jf.AppendNewLine(); jf.Append("UNION ALL"); if (indent == 0) { jf.AppendNewLine(); } DbRawCommand cmd2 = this.TranslateSelectCommand(tree.Unions[index], indent, isOutermost, context); jf.Append(cmd2.CommandText); } } #endregion #region 分页查询 if (tree.Take > 0 || tree.Skip > 0) { // 合并 WHERE result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.AppendNewLine(); jf.Append("WHERE "); if (tree.Skip > 0) { jf.AppendMember(alias, "Row_Number0"); jf.Append(" > "); jf.Append(this.Constor.GetSqlValue(tree.Skip, context)); } if (tree.Take > 0) { if (tree.Skip > 0) { jf.Append(" AND "); } jf.AppendMember(alias, "Row_Number0"); jf.Append(" <= "); jf.Append(this.Constor.GetSqlValue((tree.Skip + tree.Take), context)); } } #endregion #region Any子句 // 'Any' 子句 if (tree.HasAny) { // 产生 WHERE 子句 result.CombineFragments(); // 如果没有分页,则显式指定只查一笔记录 if (tree.Take == 0 && tree.Skip == 0) { if (tree.Wheres != null && tree.Wheres.Count > 0) { jf.Append(" AND ROWNUM <= 1"); } else { jf.AppendNewLine(); jf.Append("WHERE ROWNUM <= 1"); } } indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); } #endregion #region 还原状态 context.CurrentExpressionType = srcDbExpressionType; context.CurrentIsOutermost = srcIsOutmost; #endregion return(result); }
/// <summary> /// 创建 INSRT 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 TranslateInsertCommand <T>(DbQueryInsertTree tree, ITranslateContext context) { ISqlBuilder builder = this.CreateSqlBuilder(context);; var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo <T>(); if (tree.Entity != null) { // 如果没有Sequence列,使用 INSERT ALL INTO 语法,否则就一条一条逐行写入~~ // 批量 INSERT,自增列不会自动赋值 object entity = tree.Entity; ISqlBuilder columnsBuilder = this.CreateSqlBuilder(context); ISqlBuilder valuesBuilder = this.CreateSqlBuilder(context); // 指定插入列 var members = typeRuntime.Members; if (tree.EntityColumns != null && tree.EntityColumns.Count > 0) { members = new MemberAccessorCollection(); for (int i = 0; i < tree.EntityColumns.Count; i++) { Expression curExpr = tree.EntityColumns[i]; if (curExpr.NodeType == ExpressionType.Lambda) { curExpr = (curExpr as LambdaExpression).Body.ReduceUnary(); } if (curExpr.NodeType != ExpressionType.MemberAccess) { throw new XFrameworkException("Can't read field name from expression {0}", tree.EntityColumns[i]); } MemberExpression member = curExpr as MemberExpression; string name = member.Member.Name; members[name] = typeRuntime.Members[name]; } } // 自增列参数 IDbDataParameter seqParameter = null; // 自增列标记 ColumnAttribute seqColumn = null; foreach (var item in members) { var m = item as FieldAccessorBase; if (m == null || !m.IsDbField) { continue; } columnsBuilder.AppendMember(null, m.Member, typeRuntime.Type); columnsBuilder.Append(','); if (m == typeRuntime.Identity) { seqColumn = m.Column; if (tree.Bulk == null) { // 非批量INSERT,产生一个 OUTPUT 类型的参数 string parameterName = string.Format("{0}{1}{2}", this.ParameterPrefix, AppConst.PARAMETER_NAME_PRIFIX, context.Parameters.Count); seqParameter = this.DbProvider.CreateParameter(parameterName, -1, direction: ParameterDirection.Output); context.Parameters.Add(seqParameter); valuesBuilder.Append(seqParameter.ParameterName); valuesBuilder.Append(','); } else { valuesBuilder.AppendMember(((OracleColumnAttribute)m.Column).SEQName); valuesBuilder.Append(".NEXTVAL"); valuesBuilder.Append(','); } } else { var value = m.Invoke(entity); string sqlExpression = this.Constor.GetSqlValueWidthDefault(value, context, m.Column); valuesBuilder.Append(sqlExpression); valuesBuilder.Append(','); } } columnsBuilder.Length -= 1; valuesBuilder.Length -= 1; if (tree.Bulk == null) { // 非批量INSERT,产生一个 OUTPUT 类型的参数 if (seqParameter != null) { seqParameter.Direction = ParameterDirection.Output; seqParameter.DbType = DbType.Int64; builder.Append("SELECT "); builder.AppendMember(((OracleColumnAttribute)seqColumn).SEQName); builder.Append(".NEXTVAL INTO "); builder.Append(seqParameter.ParameterName); builder.Append(" FROM DUAL;"); builder.AppendNewLine(); //useSEQ = true; } builder.Append("INSERT "); } else { // 批量 INSERT if (!tree.Bulk.OnlyValue || seqColumn != null) { builder.Append("INSERT "); } // 如果有自增列则不使用 INSERT ALL INTO 语法 if (!tree.Bulk.OnlyValue && seqColumn == null) { builder.Append("ALL "); } } builder.Append("INTO "); builder.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); builder.Append('('); builder.Append(columnsBuilder); builder.Append(')'); builder.AppendNewLine(); builder.AppendTab(); builder.Append("VALUES"); builder.Append('('); builder.Append(valuesBuilder); builder.Append(')'); if (tree.Bulk == null) { builder.Append(';'); } else { if (seqColumn != null) { if (tree.Bulk.IsEndPos) { builder.Append(";"); } else { builder.AppendNewLine(";"); } } else { builder.AppendNewLine(); if (tree.Bulk.IsEndPos) { builder.Append("SELECT 1 FROM DUAL;"); } } } } else if (tree.Select != null) { builder.Append("INSERT INTO "); builder.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); builder.Append('('); var srcExpressionType = context.CurrentExpressionType; var srcIsOutermost = context.CurrentIsOutermost; context.CurrentExpressionType = DbExpressionType.Insert; context.CurrentIsOutermost = false; var cmd = this.TranslateSelectCommand(tree.Select, 0, false, context) as DbSelectCommand; context.CurrentExpressionType = srcExpressionType; context.CurrentIsOutermost = srcIsOutermost; int index = 0; foreach (var column in cmd.SelectedColumns) { builder.AppendMember(column.Name); if (index < cmd.SelectedColumns.Count - 1) { builder.Append(','); } index++; } builder.Append(')'); builder.AppendNewLine(); builder.Append(cmd.CommandText); builder.Append(';'); } var result = new DbRawCommand(builder.ToString(), builder.TranslateContext != null ? builder.TranslateContext.Parameters : null, System.Data.CommandType.Text); return(result); }
/// <summary> /// 解析 SELECT 命令 /// </summary> /// <param name="tree">查询语义</param> /// <param name="indent">缩进</param> /// <param name="isOutermost">是否外层查询,内层查询不需要结束符(;)</param> /// <param name="context">解析上下文</param> /// <returns></returns> protected override DbRawCommand TranslateSelectCommand(DbQuerySelectTree tree, int indent, bool isOutermost, ITranslateContext context) { // 说明: // 1.OFFSET 前必须要有 'ORDER BY',即 'Skip' 子句前必须使用 'OrderBy' 子句 // 2.在有聚合函数的<MAX,MIN...>情况下,如果有 'Distinct' 'GroupBy' 'Skip' 'Take' 子句,则需要使用嵌套查询 // 3.'Any' 子句将翻译成 IF EXISTS... // 4.分组再分页时需要使用嵌套查询,此时子查询不需要 'OrderBy' 子句,但最外层则需要 // 5.'Skip' 'Take' 子句视为语义结束符,在其之后的子句将使用嵌套查询 // 6.导航属性中有 1:n 关系的,需要使用嵌套查询,否则分页查询会有问题 // 导航属性中有1:n关系,只统计主表 // 例:AccountList = a.Client.AccountList, var subquery = tree.Subquery as DbQuerySelectTree; if (tree.SelectHasMany && subquery != null && subquery.Aggregate != null) { tree = subquery; } var srcDbExpressionType = context.CurrentExpressionType; var srcIsOutermost = context.CurrentIsOutermost; if (srcDbExpressionType == null) { context.CurrentExpressionType = DbExpressionType.Select; } if (srcIsOutermost == null || !isOutermost) { context.CurrentIsOutermost = isOutermost; } bool useAggregate = tree.Aggregate != null; // 没有聚合函数或者使用 'Skip' 子句,则解析OrderBy // 导航属性如果使用嵌套,除非有 TOP 或者 OFFSET 子句,否则不能用ORDER BY // 第一层的表别名 string alias = context != null && !string.IsNullOrEmpty(context.AliasPrefix) ? (context.AliasPrefix + "0") : "t0"; bool useSubquery = tree.HasDistinct || tree.GroupBy != null || tree.Skip > 0 || tree.Take > 0; bool useOrderBy = (!useAggregate || tree.Skip > 0) && !tree.HasAny && (!tree.SelectHasMany || (tree.Skip > 0 || tree.Take > 0)); AliasGenerator ag = this.PrepareTableAlias(tree, context != null ? context.AliasPrefix : null); var result = new SqlServerDbSelectCommand(context, ag, tree.SelectHasMany); ISqlBuilder jf = result.JoinFragment; ISqlBuilder wf = result.WhereFragment; jf.Indent = indent; #region 嵌套查询 if (useAggregate && useSubquery) { // SELECT jf.Append("SELECT "); jf.AppendNewLine(); // SELECT COUNT(1) var visitor = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, alias); visitor.Visit(tree.Aggregate); result.AddNavMembers(visitor.NavMembers); // SELECT COUNT(1) FROM jf.AppendNewLine(); jf.Append("FROM ( "); indent += 1; jf.Indent = indent; context.CurrentIsOutermost = false; } #endregion 嵌套查询 #region 择子句 // SELECT 子句 if (jf.Indent > 0) { jf.AppendNewLine(); } if (tree.HasAny) { jf.Append("IF EXISTS("); indent += 1; jf.Indent = indent; jf.AppendNewLine(); } jf.Append("SELECT "); if (useAggregate && !useSubquery) { // 如果有聚合函数,并且不是嵌套的话,则直接使用SELECT <MAX,MIN...>,不需要解析选择的字段 jf.AppendNewLine(); var visitor = new AggregateExpressionVisitor(ag, jf, tree.GroupBy, null); visitor.Visit(tree.Aggregate); result.AddNavMembers(visitor.NavMembers); } else { // DISTINCT 子句 if (tree.HasDistinct) { jf.Append("DISTINCT "); } // TOP 子句 if (tree.Take > 0 && tree.Skip == 0) { jf.AppendFormat("TOP({0})", this.Constor.GetSqlValue(tree.Take, context)); } // Any if (tree.HasAny) { jf.Append("TOP 1 1"); } #region 字段 if (!tree.HasAny) { // SELECT 范围 var visitor = new ColumnExpressionVisitor(ag, jf, tree); visitor.Visit(tree.Select); result.SelectedColumns = visitor.SelectedColumns; result.SelectedColumnText = visitor.SelectedColumnText; result.SelectedNavs = visitor.SelectedNavDescriptors; result.AddNavMembers(visitor.NavMembers); } #endregion 字段 } #endregion 择子句 #region 顺序解析 // FROM 子句 jf.AppendNewLine(); jf.Append("FROM "); if (tree.Subquery != null) { // 子查询 jf.Append('('); DbRawCommand cmd = this.TranslateSelectCommand(tree.Subquery, indent + 1, false, context); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else if (tree.FromSql != null) { if (tree.FromSql.DbContext == null) { tree.FromSql.DbContext = context.DbContext; } DbRawSql rawSql = tree.FromSql; // 解析参数 object[] args = null; if (rawSql.Parameters != null) { args = rawSql.Parameters.Select(x => this.Constor.GetSqlValue(x, context)).ToArray(); } string sql = rawSql.CommandText; if (args != null && args.Length > 0) { sql = string.Format(sql, args); } // 子查询 jf.Append('('); var cmd = new DbRawCommand(sql, context.Parameters, CommandType.Text); jf.Append(cmd.CommandText); jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } else { var typeRuntime = TypeRuntimeInfoCache.GetRuntimeInfo(tree.From); jf.AppendTable(typeRuntime.TableSchema, typeRuntime.TableName, typeRuntime.IsTemporary); jf.Append(' '); jf.Append(alias); jf.Append(' '); bool isNoLock = ((SqlServerDbContext)context.DbContext).NoLock; if (isNoLock && !string.IsNullOrEmpty(this._widthNoLock) && !typeRuntime.IsTemporary) { jf.Append(this._widthNoLock); } } // LEFT<INNER> JOIN 子句 if (tree.Joins != null) { var visitor = new SqlServerJoinExpressionVisitor(ag, jf); visitor.Visit(tree.Joins); } wf.Indent = jf.Indent; // WHERE 子句 if (tree.Wheres != null) { var visitor = new WhereExpressionVisitor(ag, wf); visitor.Visit(tree.Wheres); result.AddNavMembers(visitor.NavMembers); } // GROUP BY 子句 if (tree.GroupBy != null) { var visitor = new GroupByExpressionVisitor(ag, wf); visitor.Visit(tree.GroupBy); result.AddNavMembers(visitor.NavMembers); } // HAVING 子句 if (tree.Havings != null) { var visitor = new HavingExpressionVisitor(ag, wf, tree.GroupBy); visitor.Visit(tree.Havings); result.AddNavMembers(visitor.NavMembers); } // ORDER 子句 if (tree.OrderBys != null && tree.OrderBys.Count > 0 && useOrderBy) { var visitor = new OrderByExpressionVisitor(ag, wf, tree.GroupBy, null); visitor.Visit(tree.OrderBys); result.AddNavMembers(visitor.NavMembers); } #endregion #region 分页查询 if (tree.Skip > 0) { if (tree.OrderBys == null || tree.OrderBys.Count == 0) { throw new XFrameworkException("The method 'OrderBy' must be called before 'Skip'."); } wf.AppendNewLine(); wf.Append("OFFSET "); wf.Append(this.Constor.GetSqlValue(tree.Skip, context)); wf.Append(" ROWS"); if (tree.Take > 0) { wf.Append(" FETCH NEXT "); wf.Append(this.Constor.GetSqlValue(tree.Take, context)); wf.Append(" ROWS ONLY "); } } #endregion 分页查询 #region 嵌套查询 if (useAggregate && useSubquery) { result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") "); jf.Append(alias); jf.Append(' '); } #endregion 嵌套查询 #region 嵌套导航 if (tree.SelectHasMany && subquery.Aggregate == null && subquery != null && subquery.OrderBys != null && subquery.OrderBys.Count > 0 && !(subquery.Skip > 0 || subquery.Take > 0)) { // TODO Include 从表,没分页,OrderBy 报错 result.CombineFragments(); var visitor = new OrderByExpressionVisitor(ag, jf, null, null); visitor.Visit(subquery.OrderBys); } #endregion 嵌套导航 #region 并集查询 // UNION 子句 if (tree.Unions != null && tree.Unions.Count > 0) { result.CombineFragments(); for (int index = 0; index < tree.Unions.Count; index++) { jf.AppendNewLine(); jf.Append("UNION ALL"); if (indent == 0) { jf.AppendNewLine(); } DbRawCommand cmd = this.TranslateSelectCommand(tree.Unions[index], indent, isOutermost, context); jf.Append(cmd.CommandText); } } #endregion 并集查询 #region Any 子句 // 'Any' 子句 if (tree.HasAny) { result.CombineFragments(); indent -= 1; jf.Indent = indent; jf.AppendNewLine(); jf.Append(") SELECT 1 ELSE SELECT 0"); } #endregion Any 子句 #region 还原状态 context.CurrentExpressionType = srcDbExpressionType; context.CurrentIsOutermost = srcIsOutermost; #endregion return(result); }