public void SimplifyFromAliases()
{
if (IsSingleFromTable)
{
var source = From[0].Source;
ReplaceSimpleSource(source, null);
}
else
{
var sources = new HashSet <DmlfSource>();
From.ForEach(x => x.GetSimpleSources(sources));
var usedAliases = new HashSet <string>();
foreach (var source in sources)
{
if (sources.Count(x => x.TableOrView == source.TableOrView) == 1)
{
// use table name as qualifier, remove alias
ReplaceSimpleSource(source, null);
}
else
{
var aliasBase = DmlfSource.GetAliasBase(source.TableOrView.Name);
string alias = DmlfSource.AllocateAlias(usedAliases, aliasBase);
ReplaceSimpleSource(source, alias);
}
}
}
}
public static DmlfColumnRef[] BuildFromArray(string[] cols, DmlfSource source)
{
return((
from c in cols select new DmlfColumnRef {
ColumnName = c, Source = source
}
).ToArray());
}
public void ReplaceSimpleSource(DmlfSource source, string newAlias)
{
source = source.GetSimpleSourceCopy();
ForEachChild(x =>
{
var src = x as DmlfSource;
if (src != null && src == source)
{
src.Alias = newAlias;
}
});
}
public List <DmlfColumnRef> GetPrimaryKey(DmlfSource src)
{
var res = new List <DmlfColumnRef>();
foreach (var fld in this)
{
var col = fld.Column;
if (col != null && fld.ResultInfo != null && fld.ResultInfo.IsKey && col.Source == src)
{
res.Add(col);
}
}
return(res);
}
public static DmlfResultField BuildFromColumn(string colname, DmlfSource src)
{
return(new DmlfResultField
{
Expr = new DmlfColumnRefExpression
{
Column = new DmlfColumnRef
{
ColumnName = colname,
Source = src,
}
},
});
}
public DmlfColumnRef GetColumnRef(DmlfSource baseSource, NameWithSchema baseTable, StructuredIdentifier columnId, DatabaseInfo db, DmlfJoinType joinType)
{
var relationId = columnId.WithoutLast;
string column = columnId.Last;
var source = AddOrFindRelation(baseSource, baseTable, relationId, db, joinType);
if (source == null)
{
return(null);
}
return(new DmlfColumnRef
{
ColumnName = column,
Source = source,
});
}
private DmlfSource DoAddOrFindRelation(DmlfSource baseSource, NameWithSchema baseTable, StructuredIdentifier relationJoined, StructuredIdentifier relationToJoin, DatabaseInfo db, DmlfJoinType joinType)
{
if (relationToJoin.IsEmpty)
{
return(baseSource);
}
string relName = relationToJoin.First;
string alias = String.Format("_REF{0}_{1}", relationJoined.NameItems.Select(x => "_" + x).CreateDelimitedText(""), relName);
var source = FindSourceByAlias(alias);
if (source == null)
{
var baseTableInfo = db.FindTable(baseTable);
var fk = baseTableInfo.ForeignKeys.FirstOrDefault(x => System.String.Compare(x.ConstraintName, relName, StringComparison.OrdinalIgnoreCase) == 0);
if (fk == null)
{
var column = baseTableInfo.FindColumn(relName);
if (column != null)
{
fk = column.GetForeignKeys().FirstOrDefault(x => x.Columns.Count == 1);
}
}
if (fk == null)
{
return(null);
}
source = new DmlfSource
{
TableOrView = fk.RefTableFullName,
Alias = alias,
};
var relation = new DmlfRelation
{
Reference = source,
JoinType = joinType,
};
for (int i = 0; i < fk.Columns.Count; i++)
{
relation.Conditions.Add(new DmlfEqualCondition
{
LeftExpr = new DmlfColumnRefExpression
{
Column = new DmlfColumnRef
{
ColumnName = fk.Columns[0].RefColumnName,
Source = baseSource,
}
},
RightExpr = new DmlfColumnRefExpression
{
Column = new DmlfColumnRef
{
ColumnName = fk.RefColumns[0].RefColumnName,
Source = source,
}
},
});
Relations.Add(relation);
}
}
if (relationToJoin.IsEmpty)
{
return(source);
}
return(DoAddOrFindRelation(source, source.TableOrView, relationJoined / relationToJoin.First, relationToJoin.WithoutFirst, db, joinType));
}
public DmlfSource AddOrFindRelation(DmlfSource baseSource, NameWithSchema baseTable, StructuredIdentifier relationId, DatabaseInfo db, DmlfJoinType joinType)
{
return(DoAddOrFindRelation(baseSource, baseTable, new StructuredIdentifier(), relationId, db, joinType));
}
