/// <summary>
/// 创建 SQL 命令
/// </summary>
/// <param name="dbQuery">查询 语句</param>
/// <param name="indent">缩进</param>
/// <param name="isOuter">是否最外层，内层查询不需要结束符(;)</param>
/// <param name="token">解析上下文参数</param>
/// <returns></returns>
public RawCommand Resolve <T>(IDbQueryable <T> dbQuery, int indent, bool isOuter, ResolveToken token)
{
// 参数化设置
if (token == null)
{
token = new ResolveToken();
}
if (!dbQuery.HasSetParameterized)
{
dbQuery.Parameterized = true;
}
if (!token.HasSetParameterized)
{
token.Parameterized = dbQuery.Parameterized;
}
if (token.Parameterized && token.Parameters == null)
{
token.Parameters = new List <IDbDataParameter>(8);
}
if (token.DbContext == null)
{
token.DbContext = dbQuery.DbContext;
}
// 解析查询语义
IDbQueryableInfo result = DbQueryParser.Parse <T>(dbQuery);
// 查询
var result_Query = result as IDbQueryableInfo_Select;
if (result_Query != null)
{
return(this.ResolveSelectCommand(result_Query, indent, isOuter, token));
}
// 新增
var result_Insert = result as IDbQueryableInfo_Insert;
if (result_Insert != null)
{
return(this.ResolveInsertCommand <T>(result_Insert, token));
}
// 更新
var result_Update = result as IDbQueryableInfo_Update;
if (result_Update != null)
{
return(this.ResolveUpdateCommand <T>(result_Update, token));
}
// 删除
var result_Delete = result as IDbQueryableInfo_Delete;
if (result_Delete != null)
{
return(this.ResolveDeleteCommand <T>(result_Delete, token));
}
throw new NotImplementedException();
}
/// <summary>
/// 创建 SQL 命令
/// </summary>
/// <param name="dbQueryable">查询 语句</param>
/// <param name="indent">缩进</param>
/// <param name="isOuter">是否最外层，内层查询不需要结束符(;)</param>
/// <param name="token">解析上下文参数</param>
/// <returns></returns>
public Command Resolve <T>(IDbQueryable <T> dbQueryable, int indent, bool isOuter, ResolveToken token)
{
// 设置该查询是否需要参数化
if (token == null)
{
token = new ResolveToken();
}
if (!((DbQueryable)dbQueryable).HasSetParameterized)
{
dbQueryable.Parameterized = true;
}
if (dbQueryable.Parameterized && token.Parameters == null)
{
token.Parameters = new List <IDbDataParameter>(8);
}
// 调试模式
if (token != null && !token.HasSetIsDebug)
{
token.IsDebug = dbQueryable.DbContext.IsDebug;
}
// 解析查询语义
IDbQueryableInfo <T> dbQueryInfo = DbQueryParser.Parse(dbQueryable);
DbQueryableInfo_Select <T> sQueryInfo = dbQueryInfo as DbQueryableInfo_Select <T>;
if (sQueryInfo != null)
{
return(this.ParseSelectCommand <T>(sQueryInfo, indent, isOuter, token));
}
DbQueryableInfo_Insert <T> nQueryInfo = dbQueryInfo as DbQueryableInfo_Insert <T>;
if (nQueryInfo != null)
{
return(this.ParseInsertCommand <T>(nQueryInfo, token));
}
DbQueryableInfo_Update <T> uQueryInfo = dbQueryInfo as DbQueryableInfo_Update <T>;
if (uQueryInfo != null)
{
return(this.ParseUpdateCommand <T>(uQueryInfo, token));
}
DbQueryableInfo_Delete <T> dQueryInfo = dbQueryInfo as DbQueryableInfo_Delete <T>;
if (dQueryInfo != null)
{
return(this.ParseDeleteCommand <T>(dQueryInfo, token));
}
throw new NotImplementedException();
}
/// <summary>
/// 创建 SQL 命令
/// </summary>
/// <param name="dbQuery">查询 语句</param>
/// <param name="indent">缩进</param>
/// <param name="isOuter">是否最外层，内层查询不需要结束符(;)</param>
/// <param name="token">解析上下文参数</param>
/// <returns></returns>
public Command Resolve <T>(IDbQueryable <T> dbQuery, int indent, bool isOuter, ResolveToken token)
{
// 设置该查询是否需要参数化
if (token == null)
{
token = new ResolveToken();
}
if (!((DbQueryable)dbQuery).HasSetParameterized)
{
dbQuery.Parameterized = true;
}
if (dbQuery.Parameterized && token.Parameters == null)
{
token.Parameters = new List <IDbDataParameter>(8);
}
// 调试模式
if (token != null && !token.HasSetIsDebug)
{
token.IsDebug = dbQuery.DbContext.IsDebug;
}
// 解析查询语义
IDbQueryableInfo <T> result = DbQueryParser.Parse(dbQuery);
// 查询
DbQueryableInfo_Select <T> result_Query = result as DbQueryableInfo_Select <T>;
if (result_Query != null)
{
return(this.ResolveSelectCommand <T>(result_Query, indent, isOuter, token));
}
// 新增
DbQueryableInfo_Insert <T> result_Insert = result as DbQueryableInfo_Insert <T>;
if (result_Insert != null)
{
return(this.ResolveInsertCommand <T>(result_Insert, token));
}
// 更新
DbQueryableInfo_Update <T> result_Update = result as DbQueryableInfo_Update <T>;
if (result_Update != null)
{
return(this.ResolveUpdateCommand <T>(result_Update, token));
}
// 删除
DbQueryableInfo_Delete <T> result_Delete = result as DbQueryableInfo_Delete <T>;
if (result_Delete != null)
{
return(this.ResolveDeleteCommand <T>(result_Delete, token));
}
throw new NotImplementedException();
}
/// <summary>
/// 创建 SQL 命令
/// </summary>
/// <param name="dbQueryable">查询 语句</param>
/// <param name="indent">缩进</param>
/// <param name="isOuter">是否最外层，内层查询不需要结束符(;)</param>
/// <param name="parameters">已存在的参数列表</param>
/// <returns></returns>
public DbCommandDefinition Resolve <T>(IDbQueryable <T> dbQueryable, int indent = 0, bool isOuter = true, List <IDbDataParameter> parameters = null)
{
// 设置该查询是否需要参数化
if (!((DbQueryable)dbQueryable).HasSetParameterized)
{
dbQueryable.Parameterized = true;
}
if (dbQueryable.Parameterized && parameters == null)
{
parameters = new List <IDbDataParameter>(8);
}
// 解析查询语义
IDbQueryableInfo <T> info = DbQueryParser.Parse(dbQueryable);
DbQueryableInfo_Select <T> sQuery = info as DbQueryableInfo_Select <T>;
if (sQuery != null)
{
return(this.ParseSelectCommand <T>(sQuery, indent, isOuter, dbQueryable.Parameterized ? parameters : null));
}
DbQueryableInfo_Insert <T> nQuery = info as DbQueryableInfo_Insert <T>;
if (nQuery != null)
{
return(this.ParseInsertCommand <T>(nQuery, dbQueryable.Parameterized ? parameters : null));
}
DbQueryableInfo_Update <T> uQuery = info as DbQueryableInfo_Update <T>;
if (uQuery != null)
{
return(this.ParseUpdateCommand <T>(uQuery, dbQueryable.Parameterized ? parameters : null));
}
DbQueryableInfo_Delete <T> dQuery = info as DbQueryableInfo_Delete <T>;
if (dQuery != null)
{
return(this.ParseDeleteCommand <T>(dQuery, dbQueryable.Parameterized ? parameters : null));
}
throw new NotImplementedException();
}
// 解析查询语义
static IDbQueryableInfo <TElement> Parse <TElement>(IDbQueryable <TElement> dbQuery, int startIndex)
{
// 目的：将query 转换成增/删/改/查
// 1、from a in context.GetTable<T>() select a 此时query里面可能没有SELECT 表达式
// 2、Take 视为一个查询的结束位，如有更多查询，应使用嵌套查询
// 3、uion 分页查询也使嵌套语义
// 4、uion 后面跟着 WHERE,GROUP BY,SELECT,JOIN语句时需要使用嵌套查询
Type type = null;
bool isDistinct = false;
bool isAny = false;
bool subQuery = false;
int? skip = null;
int? take = null;
int? outerIndex = null;
var whereExpressions = new List <Expression>(); // WHERE
var havingExpressions = new List <Expression>(); // HAVING
var joins = new List <DbExpression>(); // JOIN
var orderBys = new List <DbExpression>(); // ORDER BY
var includes = new List <DbExpression>(); // ORDER BY
var unions = new List <IDbQueryableInfo <TElement> >();
Expression selectExpression = null; // SELECT #
DbExpression insertExpression = null; // INSERT #
DbExpression updateExpression = null; // UPDATE #
DbExpression deleteExpression = null; // DELETE #
DbExpression groupByExpression = null; // GROUP BY #
DbExpression statisExpression = null; // SUM/MAX #
for (int index = startIndex; index < dbQuery.DbExpressions.Count; index++)
{
DbExpression curExpr = dbQuery.DbExpressions[index];
// Take(n)
if (take != null || (skip != null && curExpr.DbExpressionType != DbExpressionType.Take) || isDistinct || subQuery)
{
outerIndex = index;
break;
}
#region 解析片断
switch (curExpr.DbExpressionType)
{
case DbExpressionType.None:
case DbExpressionType.All:
continue;
case DbExpressionType.Any:
isAny = true;
if (curExpr.Expressions != null)
{
whereExpressions.Add(curExpr.Expressions[0]);
}
break;
case DbExpressionType.AsSubQuery:
subQuery = true;
continue;
case DbExpressionType.Union:
var uQuery = (curExpr.Expressions[0] as ConstantExpression).Value as IDbQueryable <TElement>;
var u = DbQueryParser.Parse(uQuery);
unions.Add(u);
// 如果下一个不是 union，就使用嵌套
if (index + 1 <= dbQuery.DbExpressions.Count - 1 && dbQuery.DbExpressions[index + 1].DbExpressionType != DbExpressionType.Union)
{
subQuery = true;
}
continue;
case DbExpressionType.Include:
includes.Add(curExpr);
continue;
case DbExpressionType.GroupBy:
groupByExpression = curExpr;
continue;
case DbExpressionType.GetTable:
type = (curExpr.Expressions[0] as ConstantExpression).Value as Type;
continue;
case DbExpressionType.Average:
case DbExpressionType.Min:
case DbExpressionType.Sum:
case DbExpressionType.Max:
statisExpression = curExpr;
continue;
case DbExpressionType.Count:
statisExpression = curExpr;
if (curExpr.Expressions != null)
{
whereExpressions.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Distinct:
isDistinct = true;
continue;
case DbExpressionType.First:
case DbExpressionType.FirstOrDefault:
take = 1;
if (curExpr.Expressions != null)
{
whereExpressions.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Join:
case DbExpressionType.GroupJoin:
case DbExpressionType.GroupRightJoin:
selectExpression = curExpr.Expressions[3];
joins.Add(curExpr);
continue;
case DbExpressionType.OrderBy:
case DbExpressionType.OrderByDescending:
orderBys.Add(curExpr);
continue;
case DbExpressionType.Select:
selectExpression = curExpr.Expressions != null ? curExpr.Expressions[0] : null;
continue;
case DbExpressionType.SelectMany:
selectExpression = curExpr.Expressions[1];
if (CheckSelectMany(dbQuery.DbExpressions, curExpr, startIndex))
{
joins.Add(curExpr);
}
continue;
case DbExpressionType.Single:
case DbExpressionType.SingleOrDefault:
take = 1;
if (curExpr.Expressions != null)
{
whereExpressions.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Skip:
skip = (int)(curExpr.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.Take:
take = (int)(curExpr.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.ThenBy:
case DbExpressionType.ThenByDescending:
orderBys.Add(curExpr);
continue;
case DbExpressionType.Where:
var predicate = groupByExpression == null ? whereExpressions : havingExpressions;
if (curExpr.Expressions != null)
{
predicate.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Insert:
insertExpression = curExpr;
continue;
case DbExpressionType.Update:
updateExpression = curExpr;
continue;
case DbExpressionType.Delete:
deleteExpression = curExpr;
continue;
default:
throw new NotSupportedException(string.Format("{0} is not support.", curExpr.DbExpressionType));
}
#endregion
}
// 没有解析到INSERT/DELETE/UPDATE/SELECT表达式，并且没有相关统计函数，则默认选择FromType的所有字段
bool useFullFields = insertExpression == null && deleteExpression == null && updateExpression == null && selectExpression == null && statisExpression == null;
if (useFullFields)
{
selectExpression = Expression.Constant(type ?? typeof(TElement));
}
var sQueryInfo = new DbQueryableInfo_Select <TElement>();
sQueryInfo.FromType = type;
sQueryInfo.HaveDistinct = isDistinct;
sQueryInfo.HaveAny = isAny;
sQueryInfo.Joins = joins;
sQueryInfo.OrderBys = orderBys;
sQueryInfo.GroupByExpression = groupByExpression;
sQueryInfo.StatisExpression = statisExpression;
sQueryInfo.Unions = unions;
sQueryInfo.Includes = includes;
sQueryInfo.Skip = skip != null ? skip.Value : 0;
sQueryInfo.Take = take != null ? take.Value : 0;
sQueryInfo.SelectExpression = new DbExpression(DbExpressionType.Select, selectExpression);
sQueryInfo.WhereExpression = new DbExpression(DbExpressionType.Where, CombineWhere(whereExpressions));
sQueryInfo.HavingExpression = new DbExpression(DbExpressionType.None, CombineWhere(havingExpressions));
sQueryInfo.SourceQuery = dbQuery;
#region 更新语义
if (updateExpression != null)
{
var uQueryInfo = new DbQueryableInfo_Update <TElement>();
var constantExpression = updateExpression.Expressions != null ? updateExpression.Expressions[0] as ConstantExpression : null;
if (constantExpression != null)
{
uQueryInfo.Entity = constantExpression.Value;
}
else
{
uQueryInfo.Expression = updateExpression.Expressions[0];
}
uQueryInfo.SelectInfo = sQueryInfo;
uQueryInfo.SourceQuery = dbQuery;
return(uQueryInfo);
}
#endregion
#region 除语义
else if (deleteExpression != null)
{
var dQueryInfo = new DbQueryableInfo_Delete <TElement>();
var constantExpression = deleteExpression.Expressions != null ? deleteExpression.Expressions[0] as ConstantExpression : null;
if (constantExpression != null)
{
dQueryInfo.Entity = constantExpression.Value;
}
dQueryInfo.SelectInfo = sQueryInfo;
dQueryInfo.SourceQuery = dbQuery;
return(dQueryInfo);
}
#endregion
#region 插入语义
else if (insertExpression != null)
{
var nQueryInfo = new DbQueryableInfo_Insert <TElement>();
if (insertExpression.Expressions != null)
{
nQueryInfo.Entity = (insertExpression.Expressions[0] as ConstantExpression).Value;
if (insertExpression.Expressions.Length > 1)
{
nQueryInfo.EntityColumns = (insertExpression.Expressions[1] as ConstantExpression).Value as IList <Expression>;
}
}
nQueryInfo.SelectInfo = sQueryInfo;
nQueryInfo.Bulk = dbQuery.Bulk;
nQueryInfo.SourceQuery = dbQuery;
dbQuery.DbQueryInfo = nQueryInfo;
return(nQueryInfo);
}
#endregion
#region 择语义
else if (selectExpression != null)
{
// 检查嵌套查询语义
sQueryInfo = DbQueryParser.TryBuildOutQuery(sQueryInfo);
// 查询来源
sQueryInfo.SourceQuery = dbQuery;
}
#endregion
#region 嵌套语义
// 解析嵌套查询
if (outerIndex != null)
{
var outQuery = DbQueryParser.Parse <TElement>(dbQuery, outerIndex.Value);
var nQuery = outQuery as DbQueryableInfo_Insert <TElement>;
var uQuery = outQuery as DbQueryableInfo_Update <TElement>;
if (nQuery != null)
{
if (nQuery.SelectInfo != null)
{
nQuery.SelectInfo.SubQueryInfo = sQueryInfo;
}
else
{
nQuery.SelectInfo = sQueryInfo;
}
nQuery.SourceQuery = dbQuery;
return(nQuery);
}
else if (uQuery != null)
{
if (uQuery.SelectInfo != null)
{
uQuery.SelectInfo.SubQueryInfo = sQueryInfo;
}
else
{
uQuery.SelectInfo = sQueryInfo;
}
uQuery.SourceQuery = dbQuery;
return(uQuery);
}
else
{
var rootQuery = outQuery;
while (rootQuery.SubQueryInfo != null)
{
rootQuery = rootQuery.SubQueryInfo;
}
rootQuery.SubQueryInfo = sQueryInfo;
outQuery.SourceQuery = dbQuery;
// 如果外层是统计，内层没有分页，则不需要排序
rootQuery = outQuery;
while (rootQuery.SubQueryInfo != null)
{
var myOutQuery = rootQuery as IDbQueryableInfo_Select;
var mySubQuery = rootQuery.SubQueryInfo as IDbQueryableInfo_Select;
// 没有分页的嵌套统计，不需要排序
if (myOutQuery.StatisExpression != null && !(mySubQuery.Take > 0 || mySubQuery.Skip > 0) && mySubQuery.OrderBys.Count > 0)
{
mySubQuery.OrderBys = new List <DbExpression>(0);
}
// 继续下一轮迭代
rootQuery = rootQuery.SubQueryInfo;
}
return(outQuery);
}
}
#endregion
// 查询表达式
return(sQueryInfo);
}
/// <summary>
/// 解析查询语义
/// </summary>
internal static IDbQueryableInfo <TElement> Parse <TElement>(IDbQueryable <TElement> dbQuery)
{
return(DbQueryParser.Parse(dbQuery, 0));
}
// 构造由一对多关系产生的嵌套查询
static IDbQueryableInfo_Select ParseOutQuery(IDbQueryableInfo_Select dbQuery)
{
// @havePaging 是否有分页信息
if (dbQuery == null || dbQuery.Select == null)
{
return(dbQuery);
}
Expression select = dbQuery.Select.Expressions[0];
List <DbExpression> includes = dbQuery.Includes;
Type fromType = dbQuery.FromType;
// 解析导航属性 如果有 1:n 的导航属性，那么查询的结果集的主记录将会有重复记录
// 这时就需要使用嵌套语义，先查主记录，再关联导航记录
Expression myExpression = select;
var lambdaExpression = myExpression as LambdaExpression;
if (lambdaExpression != null)
{
myExpression = lambdaExpression.Body;
}
var initExpression = myExpression as MemberInitExpression;
var newExpression = myExpression as NewExpression;
bool hasMany = DbQueryParser.IsHasMany(includes);
if (!hasMany)
{
hasMany = initExpression != null && IsHasMany(initExpression);
}
#region 嵌套语义
if (hasMany)
{
newExpression = initExpression != null ? initExpression.NewExpression : newExpression;
List <MemberBinding> bindings = new List <MemberBinding>();
if (initExpression != null)
{
bindings = initExpression.Bindings.ToList(x => x, x => TypeUtils.IsPrimitiveType((x.Member as System.Reflection.PropertyInfo).PropertyType));
}
if (newExpression != null || bindings.Count() > 0)
{
// 简化内层选择器，只选择最小字段，不选择导航字段，导航字段在外层加进去
initExpression = Expression.MemberInit(newExpression, bindings);
lambdaExpression = Expression.Lambda(initExpression, lambdaExpression.Parameters);
dbQuery.Select = new DbExpression(DbExpressionType.Select, lambdaExpression);
}
dbQuery.IsParsedByMany = true;
dbQuery.Includes = new List <DbExpression>(0);
var result_Query = new DbQueryableInfo_Select();
result_Query.FromType = fromType;
result_Query.Subquery = dbQuery;
result_Query.Joins = new List <DbExpression>(0);
result_Query.OrderBys = new List <DbExpression>(0);
result_Query.Includes = includes;
result_Query.HasMany = true;
result_Query.Select = new DbExpression(DbExpressionType.Select, select);
#region 排序
if (dbQuery.OrderBys.Count > 0)
{
// 是否有分页
bool havePaging = (dbQuery.Take > 0 || dbQuery.Skip > 0);
if (!havePaging)
{
// 如果没有分页，则OrderBy需要放在外层
result_Query.OrderBys = dbQuery.OrderBys;
dbQuery.OrderBys = new List <DbExpression>(0);
}
else
{
// 如果有分页，只有主表/用到的1:1从表放在内层，其它放在外层
List <DbExpression> innerOrderBy = null;
foreach (var dbExpression in dbQuery.OrderBys)
{
hasMany = IsHasMany(dbExpression.Expressions[0] as LambdaExpression);
if (!hasMany)
{
if (innerOrderBy == null)
{
innerOrderBy = new List <DbExpression>();
}
innerOrderBy.Add(dbExpression);
}
}
if (innerOrderBy != null && innerOrderBy.Count > 0)
{
result_Query.OrderBys = dbQuery.OrderBys;
dbQuery.OrderBys = innerOrderBy;
}
}
}
#endregion
#region 分组
if (dbQuery.GroupBy != null)
{
// 查看外层是否需要重新构造选择器。如果有分组并且有聚合函数，则需要重新构造选择器。否则外层解析不了聚合函数
// demo => line 1280
bool newSelector = bindings.Any(x => ((MemberAssignment)x).Expression.NodeType == ExpressionType.Call) || newExpression.Arguments.Any(x => x.NodeType == ExpressionType.Call);
if (newSelector)
{
ParameterExpression newParameter = null;
List <DbExpression> dbExpressions = null;
if (result_Query.Includes != null && result_Query.Includes.Count > 0)
{
dbExpressions = result_Query.Includes;
}
else if (result_Query.OrderBys != null && result_Query.OrderBys.Count > 0)
{
dbExpressions = result_Query.OrderBys;
}
if (dbExpressions != null && dbExpressions.Count > 0)
{
newParameter = (dbExpressions[0].Expressions[0] as LambdaExpression).Parameters[0];
}
// 1对多导航嵌套查询外层的的第一个表别名固定t0，参数名可随意
var parameterExpression = newParameter != null ? newParameter : Expression.Parameter(newExpression.Type, "__g");
bindings = bindings.ToList(x => (MemberBinding)Expression.Bind(x.Member, Expression.MakeMemberAccess(parameterExpression, x.Member)));
List <Expression> arguments = null;
if (newExpression.Members != null)
{
arguments = new List <Expression>(newExpression.Arguments.Count);
for (int i = 0; i < newExpression.Arguments.Count; i++)
{
var member = newExpression.Members[i];
var arg = Expression.MakeMemberAccess(parameterExpression, member);
arguments.Add(arg);
}
}
newExpression = Expression.New(newExpression.Constructor, arguments, newExpression.Members);
initExpression = Expression.MemberInit(newExpression, bindings);
lambdaExpression = Expression.Lambda(initExpression, parameterExpression);
result_Query.Select = new DbExpression(DbExpressionType.Select, lambdaExpression);
}
}
#endregion
dbQuery = result_Query;
}
#endregion
return(dbQuery);
}
// 解析查询语义
static IDbQueryableInfo Parse(IDbQueryable source, Type elmentType, int startIndex)
{
// 目的：将query 转换成增/删/改/查
// 1、from a in context.GetTable<T>() select a 此时query里面可能没有SELECT 表达式
// 2、Take 视为一个查询的结束位，如有更多查询，应使用嵌套查询
// 3、uion 分页查询也使嵌套语义
// 4、uion 后面跟着 WHERE,GROUP BY,SELECT,JOIN语句时需要使用嵌套查询
Type fromType = null;
bool isDistinct = false;
bool isAny = false;
bool subQuery = false;
int? skip = null;
int? take = null;
int? outerIndex = null;
var conditions = new List <Expression>(); // WHERE
var havings = new List <Expression>(); // HAVING
var joins = new List <DbExpression>(); // JOIN
var orderBys = new List <DbExpression>(); // ORDER BY
var includes = new List <DbExpression>(); // ORDER BY
var unions = new List <IDbQueryableInfo_Select>(); // UNION ALL
Expression select = null; // SELECT #
DbExpression insert = null; // INSERT #
DbExpression update = null; // UPDATE #
DbExpression delete = null; // DELETE #
DbExpression group = null; // GROUP BY #
DbExpression aggregate = null; // SUM&MAX #
for (int index = startIndex; index < source.DbExpressions.Count; index++)
{
DbExpression item = source.DbExpressions[index];
// Take(n)
if (take != null || (skip != null && item.DbExpressionType != DbExpressionType.Take) || isDistinct || subQuery)
{
outerIndex = index;
break;
}
#region 解析片断
switch (item.DbExpressionType)
{
case DbExpressionType.None:
case DbExpressionType.All:
continue;
case DbExpressionType.Any:
isAny = true;
if (item.Expressions != null)
{
conditions.Add(item.Expressions[0]);
}
break;
case DbExpressionType.AsSubquery:
subQuery = true;
continue;
case DbExpressionType.Union:
var constExpression = item.Expressions[0] as ConstantExpression;
var uQuery = constExpression.Value as IDbQueryable;
var u = DbQueryParser.Parse(uQuery, constExpression.Type.GetGenericArguments()[0], 0);
unions.Add((IDbQueryableInfo_Select)u);
// 如果下一个不是 union，就使用嵌套
if (index + 1 <= source.DbExpressions.Count - 1 && source.DbExpressions[index + 1].DbExpressionType != DbExpressionType.Union)
{
subQuery = true;
}
continue;
case DbExpressionType.Include:
includes.Add(item);
continue;
case DbExpressionType.GroupBy:
group = item;
continue;
case DbExpressionType.GetTable:
fromType = (item.Expressions[0] as ConstantExpression).Value as Type;
continue;
case DbExpressionType.Average:
case DbExpressionType.Min:
case DbExpressionType.Sum:
case DbExpressionType.Max:
aggregate = item;
continue;
case DbExpressionType.Count:
aggregate = item;
if (item.Expressions != null)
{
conditions.Add(item.Expressions[0]);
}
continue;
case DbExpressionType.Distinct:
isDistinct = true;
continue;
case DbExpressionType.First:
case DbExpressionType.FirstOrDefault:
take = 1;
if (item.Expressions != null)
{
conditions.Add(item.Expressions[0]);
}
continue;
case DbExpressionType.Join:
case DbExpressionType.GroupJoin:
case DbExpressionType.GroupRightJoin:
select = item.Expressions[3];
var j = item;
// GetTable 的参数
var inner = (j.Expressions[0] as ConstantExpression).Value as IDbQueryable;
if (inner.DbExpressions.Count == 1 &&
inner.DbExpressions[0].DbExpressionType == DbExpressionType.GetTable &&
inner.DbExpressions[0].Expressions.Length == 2)
{
var expressions = new Expression[item.Expressions.Length + 1];
Array.Copy(item.Expressions, expressions, item.Expressions.Length);
expressions[expressions.Length - 1] = inner.DbExpressions[0].Expressions[1];
j = new DbExpression(item.DbExpressionType, expressions);
}
joins.Add(j);
continue;
case DbExpressionType.OrderBy:
case DbExpressionType.OrderByDescending:
orderBys.Add(item);
continue;
case DbExpressionType.Select:
select = item.Expressions != null ? item.Expressions[0] : null;
continue;
case DbExpressionType.SelectMany:
select = item.Expressions[1];
if (IsSelectMany(source.DbExpressions, item, startIndex))
{
joins.Add(item);
}
continue;
case DbExpressionType.Single:
case DbExpressionType.SingleOrDefault:
take = 1;
if (item.Expressions != null)
{
conditions.Add(item.Expressions[0]);
}
continue;
case DbExpressionType.Skip:
skip = (int)(item.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.Take:
take = (int)(item.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.ThenBy:
case DbExpressionType.ThenByDescending:
orderBys.Add(item);
continue;
case DbExpressionType.Where:
var predicate = group == null ? conditions : havings;
if (item.Expressions != null)
{
predicate.Add(item.Expressions[0]);
}
continue;
case DbExpressionType.Insert:
insert = item;
continue;
case DbExpressionType.Update:
update = item;
continue;
case DbExpressionType.Delete:
delete = item;
continue;
default:
throw new NotSupportedException(string.Format("{0} is not support.", item.DbExpressionType));
}
#endregion
}
// 没有解析到INSERT/DELETE/UPDATE/SELECT表达式，并且没有相关聚合函数，则默认选择 FromEntityType 的所有字段
bool @zero = insert == null && delete == null && update == null && select == null && aggregate == null;
if (@zero)
{
select = Expression.Constant(fromType ?? elmentType);
}
IDbQueryableInfo_Select result_Query = new DbQueryableInfo_Select();
result_Query.FromType = fromType;
result_Query.HasDistinct = isDistinct;
result_Query.HasAny = isAny;
result_Query.Joins = joins;
result_Query.OrderBys = orderBys;
result_Query.GroupBy = group;
result_Query.Aggregate = aggregate;
result_Query.Unions = unions;
result_Query.Includes = includes;
result_Query.Skip = skip != null ? skip.Value : 0;
result_Query.Take = take != null ? take.Value : 0;
result_Query.Select = new DbExpression(DbExpressionType.Select, select);
result_Query.Where = new DbExpression(DbExpressionType.Where, CombineCondition(conditions));
result_Query.Having = new DbExpression(DbExpressionType.Having, CombineCondition(havings));
#region 更新语义
if (update != null)
{
var result_Update = new DbQueryableInfo_Update();
var constantExpression = update.Expressions != null ? update.Expressions[0] as ConstantExpression : null;
if (constantExpression != null)
{
result_Update.Entity = constantExpression.Value;
}
else
{
result_Update.Expression = update.Expressions[0];
}
result_Update.Query = result_Query;
return(result_Update);
}
#endregion
#region 除语义
else if (delete != null)
{
var result_Delete = new DbQueryableInfo_Delete();
var constantExpression = delete.Expressions != null ? delete.Expressions[0] as ConstantExpression : null;
if (constantExpression != null)
{
result_Delete.Entity = constantExpression.Value;
}
result_Delete.Query = result_Query;
return(result_Delete);
}
#endregion
#region 插入语义
else if (insert != null)
{
var result_Insert = new DbQueryableInfo_Insert();
if (insert.Expressions != null)
{
result_Insert.Entity = (insert.Expressions[0] as ConstantExpression).Value;
if (insert.Expressions.Length > 1)
{
result_Insert.EntityColumns = (insert.Expressions[1] as ConstantExpression).Value as IList <Expression>;
}
}
result_Insert.Query = result_Query;
result_Insert.Bulk = source.Bulk;
return(result_Insert);
}
#endregion
#region 择语义
else if (select != null)
{
// 检查嵌套查询语义
result_Query = DbQueryParser.ParseOutQuery(result_Query);
}
#endregion
#region 嵌套语义
// 解析嵌套查询
if (outerIndex != null)
{
// todo => elementType ???
var outQuery = DbQueryParser.Parse(source, elmentType, outerIndex.Value);
var result_Insert = outQuery as DbQueryableInfo_Insert;
var result_Update = outQuery as DbQueryableInfo_Update;
var result_Delete = outQuery as DbQueryableInfo_Delete;
if (result_Insert != null)
{
if (result_Insert.Query != null)
{
result_Insert.Query.Subquery = result_Query;
}
else
{
result_Insert.Query = result_Query;
}
return(result_Insert);
}
else if (result_Update != null)
{
if (result_Update.Query != null)
{
result_Update.Query.Subquery = result_Query;
}
else
{
result_Update.Query = result_Query;
}
return(result_Update);
}
else if (result_Delete != null)
{
if (result_Delete.Query != null)
{
result_Delete.Query.Subquery = result_Query;
}
else
{
result_Delete.Query = result_Query;
}
return(result_Delete);
}
else
{
// ?? what
var iterator = (IDbQueryableInfo_Select)outQuery;
while (iterator.Subquery != null)
{
iterator = iterator.Subquery;
}
iterator.Subquery = result_Query;
// 如果外层是统计，内层没有分页，则不需要排序
iterator = (IDbQueryableInfo_Select)outQuery;
while (iterator.Subquery != null)
{
var myOutQuery = iterator as IDbQueryableInfo_Select;
var mySubQuery = iterator.Subquery as IDbQueryableInfo_Select;
// 没有分页的嵌套统计，不需要排序
if (myOutQuery.Aggregate != null && !(mySubQuery.Take > 0 || mySubQuery.Skip > 0) && mySubQuery.OrderBys.Count > 0)
{
mySubQuery.OrderBys = new List <DbExpression>(0);
}
// 继续下一轮迭代
iterator = iterator.Subquery;
}
return(outQuery);
}
}
#endregion
// 查询表达式
return((IDbQueryableInfo)result_Query);
}
/// <summary>
/// 解析查询语义
/// </summary>
internal static IDbQueryableInfo Parse <TElement>(IDbQueryable <TElement> source)
{
return(DbQueryParser.Parse(source, typeof(TElement), 0));
}
// 解析查询语义
static IDbQueryableInfo <TElement> Parse <TElement>(IDbQueryable <TElement> dbQuery, int startIndex)
{
// 目的：将query 转换成增/删/改/查
// 1、from a in context.GetTable<T>() select a 此时query里面可能没有SELECT 表达式
// 2、Take 视为一个查询的结束位，如有更多查询，应使用嵌套查询
// 3、Uion 分页查询也使嵌套语义
Type type = null;
bool isDistinct = false;
bool isAny = false;
bool isSubQuery = false;
int? skip = null;
int? take = null;
int? outerIndex = null;
List <Expression> where = new List <Expression>(); // WHERE
List <Expression> having = new List <Expression>(); // HAVING
List <DbExpression> join = new List <DbExpression>(); // JOIN
List <DbExpression> orderBy = new List <DbExpression>(); // ORDER BY
List <DbExpression> include = new List <DbExpression>(); // ORDER BY
List <IDbQueryableInfo <TElement> > union = new List <IDbQueryableInfo <TElement> >();
Expression select = null; // SELECT #
DbExpression insert = null; // INSERT #
DbExpression update = null; // UPDATE #
DbExpression delete = null; // DELETE #
DbExpression groupBy = null; // GROUP BY #
DbExpression statis = null; // SUM/MAX #
for (int index = startIndex; index < dbQuery.DbExpressions.Count; ++index)
{
DbExpression curExpr = dbQuery.DbExpressions[index];
// Take(n)
if (take != null || (skip != null && curExpr.DbExpressionType != DbExpressionType.Take) || isDistinct || isSubQuery)
{
outerIndex = index;
break;
}
#region 分析语义
switch (curExpr.DbExpressionType)
{
case DbExpressionType.None:
case DbExpressionType.All:
continue;
case DbExpressionType.Any:
isAny = true;
if (curExpr.Expressions != null)
{
where.Add(curExpr.Expressions[0]);
}
break;
case DbExpressionType.AsSubQuery:
isSubQuery = true;
//if (curExp.Expressions != null) where.Add(curExp.Expressions[0]);
break;
case DbExpressionType.Union:
var uQuery = (curExpr.Expressions[0] as ConstantExpression).Value as IDbQueryable <TElement>;
var u = DbQueryParser.Parse(uQuery);
union.Add(u);
continue;
case DbExpressionType.Include:
include.Add(curExpr);
continue;
case DbExpressionType.GroupBy:
groupBy = curExpr;
continue;
case DbExpressionType.GetTable:
type = (curExpr.Expressions[0] as ConstantExpression).Value as Type;
continue;
case DbExpressionType.Average:
case DbExpressionType.Min:
case DbExpressionType.Sum:
case DbExpressionType.Max:
statis = curExpr;
continue;
case DbExpressionType.Count:
statis = curExpr;
if (curExpr.Expressions != null)
{
where.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Distinct:
isDistinct = true;
continue;
case DbExpressionType.First:
case DbExpressionType.FirstOrDefault:
take = 1;
if (curExpr.Expressions != null)
{
where.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Join:
case DbExpressionType.GroupJoin:
case DbExpressionType.GroupRightJoin:
select = curExpr.Expressions[3];
join.Add(curExpr);
continue;
case DbExpressionType.OrderBy:
case DbExpressionType.OrderByDescending:
orderBy.Add(curExpr);
continue;
case DbExpressionType.Select:
select = curExpr.Expressions != null ? curExpr.Expressions[0] : null;
continue;
case DbExpressionType.SelectMany:
select = curExpr.Expressions[1];
if (CheckSelectMany(dbQuery.DbExpressions, curExpr, startIndex))
{
join.Add(curExpr);
}
continue;
case DbExpressionType.Single:
case DbExpressionType.SingleOrDefault:
take = 1;
if (curExpr.Expressions != null)
{
where.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Skip:
skip = (int)(curExpr.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.Take:
take = (int)(curExpr.Expressions[0] as ConstantExpression).Value;
continue;
case DbExpressionType.ThenBy:
case DbExpressionType.ThenByDescending:
orderBy.Add(curExpr);
continue;
case DbExpressionType.Where:
var predicate = groupBy == null ? where : having;
if (curExpr.Expressions != null)
{
predicate.Add(curExpr.Expressions[0]);
}
continue;
case DbExpressionType.Insert:
insert = curExpr;
continue;
case DbExpressionType.Update:
update = curExpr;
continue;
case DbExpressionType.Delete:
delete = curExpr;
continue;
default:
throw new NotSupportedException(string.Format("{0} is not support.", curExpr.DbExpressionType));
}
#endregion
}
// 没有解析到INSERT/DELETE/UPDATE/SELECT表达式，并且没有相关统计函数，则默认选择FromType的所有字段
bool useFullColumns = insert == null && delete == null && update == null && select == null && statis == null;
if (useFullColumns)
{
select = Expression.Constant(type ?? typeof(TElement));
}
var sQuery = new DbQueryableInfo_Select <TElement>();
sQuery.FromType = type;
sQuery.HaveDistinct = isDistinct;
sQuery.HaveAny = isAny;
sQuery.Join = join;
sQuery.OrderBy = orderBy;
sQuery.GroupBy = groupBy;
sQuery.Statis = statis;
sQuery.Union = union;
sQuery.Include = include;
sQuery.Skip = skip != null ? skip.Value : 0;
sQuery.Take = take != null ? take.Value : 0;
sQuery.Select = new DbExpression(DbExpressionType.Select, select);
sQuery.Where = new DbExpression(DbExpressionType.Where, DbQueryParser.CombineWhere(where));
sQuery.Having = new DbExpression(DbExpressionType.None, DbQueryParser.CombineWhere(having));
sQuery.SourceQuery = dbQuery;
// 更新
if (update != null)
{
var uQuery = new DbQueryableInfo_Update <TElement>();
ConstantExpression expression2 = update.Expressions != null ? update.Expressions[0] as ConstantExpression : null;
if (expression2 != null)
{
uQuery.Entity = expression2.Value;
}
else
{
uQuery.Expression = update.Expressions[0];
}
uQuery.SelectInfo = sQuery;
uQuery.SourceQuery = dbQuery;
return(uQuery);
}
// 删除
if (delete != null)
{
var dQuery = new DbQueryableInfo_Delete <TElement>();
ConstantExpression expression2 = delete.Expressions != null ? delete.Expressions[0] as ConstantExpression : null;
if (expression2 != null)
{
dQuery.Entity = expression2.Value;
}
dQuery.SelectInfo = sQuery;
dQuery.SourceQuery = dbQuery;
return(dQuery);
}
// 新增
if (insert != null)
{
var nQuery = new DbQueryableInfo_Insert <TElement>();
if (insert.Expressions != null)
{
nQuery.Entity = (insert.Expressions[0] as ConstantExpression).Value;
if (insert.Expressions.Length > 1)
{
nQuery.EntityColumns = (insert.Expressions[1] as ConstantExpression).Value as IList <Expression>;
}
}
nQuery.SelectInfo = sQuery;
nQuery.Bulk = dbQuery.Bulk;
nQuery.SourceQuery = dbQuery;
dbQuery.DbQueryInfo = nQuery;
return(nQuery);
}
// 如果有一对多的导航关系，则产生嵌套语义的查询
if (select != null)
{
// 如果有uion但是没分页，应去掉orderby子句
if (sQuery.Union.Count > 0 && !(sQuery.Take > 0 || sQuery.Skip > 0))
{
sQuery.OrderBy = new List <DbExpression>();
}
// 检查嵌套查询语义
sQuery = DbQueryParser.TryBuilOuter(sQuery);
sQuery.SourceQuery = dbQuery;
}
// 解析嵌套查询
if (outerIndex != null)
{
var outQuery = DbQueryParser.Parse <TElement>(dbQuery, outerIndex.Value);
var nQuery = outQuery as DbQueryableInfo_Insert <TElement>;
var uQuery = outQuery as DbQueryableInfo_Update <TElement>;
if (nQuery != null)
{
if (nQuery.SelectInfo != null)
{
nQuery.SelectInfo.SubQueryInfo = sQuery;
}
else
{
nQuery.SelectInfo = sQuery;
}
nQuery.SourceQuery = dbQuery;
return(nQuery);
}
else if (uQuery != null)
{
if (uQuery.SelectInfo != null)
{
uQuery.SelectInfo.SubQueryInfo = sQuery;
}
else
{
uQuery.SelectInfo = sQuery;
}
uQuery.SourceQuery = dbQuery;
return(uQuery);
}
else
{
outQuery.SubQueryInfo = sQuery;
outQuery.SourceQuery = dbQuery;
return(outQuery);
}
}
// 查询表达式
return(sQuery);
}
/// <summary>
/// 解析查询语义
/// </summary>
public override IDbQueryableInfo Parse()
{
return(DbQueryParser.Parse(this));
}
/// <summary>
/// 解析查询语义
/// </summary>
public override IDbQueryableInfo Parse(int startIndex = 0)
{
return(DbQueryParser.Parse(this));
}