// 获取 LEFT JOIN / INNER JOIN 子句关联表的的别名
private void GetLfInJoinAlias(DbExpression exp, TableAliasCache aliases)
{
Type type = exp.Expressions[0].Type.GetGenericArguments()[0];
string name = TypeRuntimeInfoCache.GetRuntimeInfo(type).TableName;
// on a.Name equals b.Name 或 on new{ Name = a.Name,Id=a.Id } equals new { Name = b.Name,Id=b.Id }
LambdaExpression left = exp.Expressions[1] as LambdaExpression;
LambdaExpression right = exp.Expressions[2] as LambdaExpression;
NewExpression body1 = left.Body as NewExpression;
if (body1 == null)
{
aliases.GetTableAlias(exp.Expressions[1]);
string alias = aliases.GetTableAlias(exp.Expressions[2]);
// 记录显示指定的LEFT JOIN 表别名
aliases.AddOrUpdateJoinTableAlias(name, alias);
}
else
{
NewExpression body2 = right.Body as NewExpression;
for (int index = 0; index < body1.Arguments.Count; ++index)
{
aliases.GetTableAlias(body1.Arguments[index]);
string alias = aliases.GetTableAlias(body2.Arguments[index]);
// 记录显示指定的LEFT JOIN 表别名
aliases.AddOrUpdateJoinTableAlias(name, alias);
}
}
}
/// <summary>
/// 追加列名
/// </summary>
/// <param name="aliases">表别名</param>
/// <param name="expression">列名表达式</param>
/// <returns>返回解析到的表别名</returns>
public string AppendMember(TableAliasCache aliases, Expression expression)
{
Expression exp = expression;
LambdaExpression lambdaExpression = exp as LambdaExpression;
if (lambdaExpression != null)
{
exp = lambdaExpression.Body;
}
MemberExpression memExp = exp as MemberExpression;
if (expression.NodeType == ExpressionType.Constant || memExp.Expression.NodeType == ExpressionType.Constant)
{
PartialVisitor visitor = new PartialVisitor();
var eval = visitor.Eval(memExp ?? expression);
string value = eval.NodeType == ExpressionType.Constant
? ExpressionVisitorBase.GetSqlValue((eval as ConstantExpression).Value)
: string.Empty;
_builder.Append(value);
return(value);
}
else
{
string alias = aliases == null ? null : aliases.GetTableAlias(memExp);
this.AppendMember(alias, memExp.Member.Name);
return(alias);
}
}
/// <summary>
/// 初始化 <see cref="OrderByExpressionVisitor"/> 类的新实例
/// </summary>
public OrderByExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, List <DbExpression> qOrder, DbExpression groupBy = null, string alias = null)
: base(provider, aliases, null, false)
{
_qOrder = qOrder;
_aliases = aliases;
_groupBy = groupBy;
_alias = alias;
}
// 获取 CROSS JOIN 子句关联表的的别名
private void GetCrossJoinAlias(DbExpression exp, TableAliasCache aliases)
{
LambdaExpression lambdaExp = exp.Expressions[1] as LambdaExpression;
for (int index = 0; index < lambdaExp.Parameters.Count; ++index)
{
aliases.GetTableAlias(lambdaExp.Parameters[index]);
}
}
/// <summary>
/// 初始化 <see cref="StatisExpressionVisitor"/> 类的新实例
/// </summary>
public StatisExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, DbExpression statis, DbExpression groupBy = null, string alias = null)
: base(provider, aliases, statis.Expressions != null ? statis.Expressions[0] : null, false)
{
_provider = provider;
_aliases = aliases;
_statis = statis;
_groupBy = groupBy;
_alias = alias;
}
/// <summary>
/// 初始化 <see cref="ExpressionVisitorBase"/> 类的新实例
/// </summary>
public ExpressionVisitorBase(DbQueryProviderBase provider, TableAliasCache aliases, Expression exp, bool useNominate = true)
{
_provider = provider;
_aliases = aliases;
_navigations = new Dictionary <string, MemberExpression>();
_expression = exp;
//var visitor = new PartialVisitor();
//_expression = useNominate ? visitor.Eval(exp) : exp;
}
/// <summary>
/// 实例化 <see cref="Builder" /> 的新实例
/// </summary>
/// <param name="escCharLeft">如 [</param>
/// <param name="escCharRight">如 ]</param>
/// <param name="aliases">别名</param>
public Builder(char escCharLeft, char escCharRight, TableAliasCache aliases)
{
_escCharLeft = escCharLeft;
_escCharRight = escCharRight;
_aliases = aliases;
_navigations = new Dictionary <string, MemberExpression>();
_joinFragment = new SqlBuilder(escCharLeft, escCharRight);
_whereFragment = new SqlBuilder(escCharLeft, escCharRight);
}
/// <summary>
/// 初始化 <see cref="ColumnExpressionVisitor"/> 类的新实例
/// </summary>
public ColumnExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, DbExpression exp, DbExpression groupBy = null, bool mOnly = false)
: base(provider, aliases, exp.Expressions != null ? exp.Expressions[0] : null)
{
_provider = provider;
_aliases = aliases;
_groupBy = groupBy;
_mOnly = mOnly;
_columns = new Dictionary <string, Column>();
_navDescriptors = new ColumnNavDescriptorCollection();
_navDescriptorKeys = new List <string>(10);
}
// LEFT OR INNER JOIN
private void AppendLfInJoin(SqlBuilder builder, DbExpression exp, TableAliasCache aliases)
{
// [TableName]
//var constExp = exp.Expressions[0] as ConstantExpression;
//constExp.Type.GetGenericArguments()[0]
//var queryable = constExp.Value as IDbQueryable;
//var innerExp = queryable.DbExpressions[0];
//if (innerExp.DbExpressionType != DbExpressionType.GetTable) throw new XfwException("inner expression must be GetTable<T> expression");
//Type type = (innerExp.Expression as ConstantExpression).Value as Type;
Type type = exp.Expressions[0].Type.GetGenericArguments()[0];
builder.Append(' ');
builder.AppendMember(TypeRuntimeInfoCache.GetRuntimeInfo(type).TableName);
LambdaExpression left = exp.Expressions[1] as LambdaExpression;
LambdaExpression right = exp.Expressions[2] as LambdaExpression;
NewExpression body1 = left.Body as NewExpression;
NewExpression body2 = right.Body as NewExpression;
// t0(t1)
string alias = body1 == null
? aliases.GetTableAlias(exp.Expressions[2])
: aliases.GetTableAlias(body2.Arguments[0]);
builder.Append(' ');
builder.Append(alias);
builder.Append(' ');
// ON a.Name = b.Name AND a.Id = b.Id
builder.Append("ON ");
if (body1 == null)
{
builder.AppendMember(aliases, left.Body.ReduceUnary());
builder.Append(" = ");
builder.AppendMember(aliases, right.Body.ReduceUnary());
}
else
{
for (int index = 0; index < body1.Arguments.Count; ++index)
{
builder.AppendMember(aliases, body1.Arguments[index]);
builder.Append(" = ");
builder.AppendMember(aliases, body2.Arguments[index]);
if (index < body1.Arguments.Count - 1)
{
builder.Append(" AND ");
}
}
}
}
// Cross Join
private void AppendCrossJoin(SqlBuilder builder, DbExpression exp, TableAliasCache aliases)
{
LambdaExpression lambdaExp = exp.Expressions[1] as LambdaExpression;
Type type = lambdaExp.Parameters[1].Type;
builder.Append(' ');
builder.AppendMember(TypeRuntimeInfoCache.GetRuntimeInfo(type).TableName);
string alias = aliases.GetTableAlias(lambdaExp.Parameters[1]);
builder.Append(' ');
builder.Append(alias);
builder.Append(' ');
}
/// <summary>
/// 根据指定表达式取表别名
/// </summary>
/// <param name="exp">表达式</param>
/// <remarks>
/// t=>t.Id
/// t.Id
/// </remarks>
public string GetTableAlias(Expression exp)
{
// p=>p.p
// p=>p.Id
// p=>p.t.Id
// p.Id
// p.t.Id
// p.t
// <>h__TransparentIdentifier0.p.Id
XfwException.Check.NotNull(exp, "exp");
string key = TableAliasCache.GetTableAliasKey(exp);
return(this.GetTableAlias(key));
}
private static string GetTableAliasKey(Expression exp)
{
if (exp == null)
{
return(null);
}
Expression expression = exp;
//c
if (exp.NodeType == ExpressionType.Constant)
{
return(null);
}
// p
ParameterExpression paramExp = expression as ParameterExpression;
if (paramExp != null)
{
return(paramExp.Name);
}
// a=>a.Id
LambdaExpression lambdaExp = expression as LambdaExpression;
if (lambdaExp != null)
{
expression = lambdaExp.Body.ReduceUnary();
}
// a.Id
// t.a
// t.t.a
// t.a.Id
MemberExpression memExp = expression as MemberExpression;
if (memExp == null)
{
return(TableAliasCache.GetTableAliasKey(expression));
}
if (memExp.IsVisitable())
{
return(TableAliasCache.GetTableAliasKey(memExp.Expression));
}
return(memExp.Member.Name);
}
// 获取 JOIN 子句关联表的的别名
protected TableAliasCache PrepareAlias <T>(DbQueryableInfo_Select <T> query)
{
TableAliasCache aliases = new TableAliasCache((query.Join != null ? query.Join.Count : 0) + 1);
foreach (DbExpression exp in query.Join)
{
// [INNER/LEFT JOIN]
if (exp.DbExpressionType == DbExpressionType.GroupJoin || exp.DbExpressionType == DbExpressionType.Join)
{
this.GetLfInJoinAlias(exp, aliases);
}
else if (exp.DbExpressionType == DbExpressionType.SelectMany)
{
this.GetCrossJoinAlias(exp, aliases);
}
}
return(aliases);
}
/// <summary>
/// 实例化 <see cref="CommandDefine_Select"/> 类的新实例
/// </summary>
/// <param name="escCharLeft">如 [</param>
/// <param name="escCharRight">如 ]</param>
/// <param name="aliases">别名</param>
public CommandDefine_Select(char escCharLeft, char escCharRight, TableAliasCache aliases)
: base(string.Empty, null, System.Data.CommandType.Text)
{
_builder = new Builder(escCharLeft, escCharRight, aliases);
}
/// <summary>
/// 初始化 <see cref="HavingExpressionVisitor"/> 类的新实例
/// </summary>
public HavingExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, DbExpression having, DbExpression groupBy)
: base(provider, aliases, having.Expressions != null ? having.Expressions[0] : null)
{
_groupBy = groupBy;
_aliases = aliases;
}
/// <summary>
/// 初始化 <see cref="WhereExpressionVisitor"/> 类的新实例
/// </summary>
public WhereExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, DbExpression exp)
: base(provider, aliases, exp.Expressions != null ? exp.Expressions[0] : null)
{
_expression = base.Expression;
}
/// <summary>
/// 初始化 <see cref="GroupByExpressionVisitor"/> 类的新实例
/// </summary>
public GroupByExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, DbExpression groupBy)
: base(provider, aliases, groupBy != null ? groupBy.Expressions[0] : null, false)
{
}
/// <summary>
/// 追加列名
/// </summary>
/// <param name="expression">列名表达式</param>
/// <param name="aliases">表别名</param>
/// <returns>返回解析到的表别名</returns>
public Expression AppendMember(Expression expression, TableAliasCache aliases)
{
this.AppendMember(aliases, expression);
return(expression);
}
/// <summary>
/// 初始化 <see cref="UpdateExpressionVisitor"/> 类的新实例
/// </summary>
public UpdateExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, Expression exp)
: base(provider, aliases, exp)
{
_provider = provider;
_aliases = aliases;
}
/// <summary>
/// 初始化 <see cref="JoinExpressionVisitor"/> 类的新实例
/// </summary>
public JoinExpressionVisitor(DbQueryProviderBase provider, TableAliasCache aliases, List <DbExpression> qJoin)
: base(provider, aliases, null, false)
{
_qJoin = qJoin;
_aliases = aliases;
}
