public string GetAlias(string desiredAlias, string defaultAlias)
{
if (_aliases == null)
{
_aliases = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
}
var alias = desiredAlias;
if (string.IsNullOrEmpty(desiredAlias) || desiredAlias.Length > 25)
{
desiredAlias = defaultAlias;
alias = defaultAlias + "1";
}
for (var i = 1; ; i++)
{
if (!_aliases.Contains(alias) && !ReservedWords.IsReserved(alias))
{
_aliases.Add(alias);
break;
}
alias = desiredAlias + i;
}
return(alias);
}
internal void SetAliases()
{
_aliases = null;
Parameters.Clear();
var allAliases = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
var paramsVisited = new HashSet <SqlParameter>();
var tablesVisited = new HashSet <SqlTableSource>();
new QueryVisitor().VisitAll(this, expr =>
{
switch (expr.ElementType)
{
case QueryElementType.MergeSourceTable:
{
var source = (SqlMergeSourceTable)expr;
Utils.MakeUniqueNames(
source.SourceFields,
null,
(n, a) => !ReservedWords.IsReserved(n),
f => f.PhysicalName,
(f, n, a) => { f.PhysicalName = n; },
f =>
{
var a = f.PhysicalName;
return(a.IsNullOrEmpty()
? "c1"
: a + (a !.EndsWith("_") ? string.Empty : "_") + "1");
},
public string GetAlias(string desiredAlias, string defaultAlias)
{
if (_aliases == null)
{
_aliases = new Dictionary <string, object>();
}
var alias = desiredAlias;
if (string.IsNullOrEmpty(desiredAlias) || desiredAlias.Length > 25)
{
desiredAlias = defaultAlias;
alias = defaultAlias + "1";
}
for (var i = 1; ; i++)
{
var s = alias.ToUpper();
if (!_aliases.ContainsKey(s) && !ReservedWords.IsReserved(s))
{
_aliases.Add(s, s);
break;
}
alias = desiredAlias + i;
}
return(alias);
}
public static void PrepareQueryAndAliases(SqlStatement statement, AliasesContext?prevAliasContext, out AliasesContext newAliasContext)
{
var allAliases = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
HashSet <string>?allParameterNames = null;
HashSet <SqlParameter>? paramsVisited = null;
HashSet <SqlTableSource>?tablesVisited = null;
var newAliases = new AliasesContext();
new QueryVisitor().VisitAll(statement, expr =>
{
if (prevAliasContext != null && prevAliasContext.IsAliased(expr))
{
// Copy aliased from previous run
//
newAliases.RegisterAliased(expr);
// Remember already used aliases from previous run
if (expr.ElementType == QueryElementType.TableSource)
{
var alias = ((SqlTableSource)expr).Alias;
if (!string.IsNullOrEmpty(alias))
{
allAliases.Add(alias !);
}
}
else if (expr.ElementType == QueryElementType.SqlParameter)
{
var alias = ((SqlParameter)expr).Name;
if (!string.IsNullOrEmpty(alias))
{
allParameterNames ??= new HashSet <string>(StringComparer.OrdinalIgnoreCase);
allParameterNames.Add(alias !);
}
}
return;
}
switch (expr.ElementType)
{
case QueryElementType.MergeSourceTable:
{
var source = (SqlTableLikeSource)expr;
Utils.MakeUniqueNames(
source.SourceFields,
null,
(n, a) => !ReservedWords.IsReserved(n),
f => f.PhysicalName,
(f, n, a) => { f.PhysicalName = n; },
f =>
{
var a = f.PhysicalName;
return(a.IsNullOrEmpty()
? "c1"
: a + (a !.EndsWith("_") ? string.Empty : "_") + "1");
},
internal void SetAliases()
{
_aliases = null;
Parameters.Clear();
var allAliases = new HashSet <string>(StringComparer.OrdinalIgnoreCase);
var paramsVisited = new HashSet <SqlParameter>();
var tablesVisited = new HashSet <SqlTableSource>();
new QueryVisitor().VisitAll(this, expr =>
{
switch (expr.ElementType)
{
case QueryElementType.SqlQuery:
{
var query = (SelectQuery)expr;
if (query.IsParameterDependent)
{
IsParameterDependent = true;
}
if (query.Select.Columns.Count > 0)
{
var isRootQuery = query.ParentSelect == null;
Utils.MakeUniqueNames(query.Select.Columns.Where(c => c.Alias != "*"),
n => !ReservedWords.IsReserved(n), c => c.Alias, (c, n) =>
{
if (isRootQuery)
{
allAliases.Add(n);
}
c.Alias = n;
},
c =>
{
var a = c.Alias;
return(a.IsNullOrEmpty()
? "c1"
: a + (a.EndsWith("_") ? string.Empty : "_") + "1");
},
StringComparer.OrdinalIgnoreCase);
if (query.HasUnion)
{
for (var i = 0; i < query.Select.Columns.Count; i++)
{
var col = query.Select.Columns[i];
foreach (var t in query.Unions)
{
var union = t.SelectQuery.Select;
union.Columns[i].Alias = col.Alias;
}
}
}
}
break;
}
case QueryElementType.SqlParameter:
{
var p = (SqlParameter)expr;
if (p.IsQueryParameter)
{
if (paramsVisited.Add(p))
{
Parameters.Add(p);
}
}
else
{
IsParameterDependent = true;
}
break;
}
case QueryElementType.TableSource:
{
var table = (SqlTableSource)expr;
tablesVisited.Add(table);
break;
}
}
});
Utils.MakeUniqueNames(tablesVisited,
n => !ReservedWords.IsReserved(n), ts => ts.Alias, (ts, n) =>
{
allAliases.Add(n);
ts.Alias = n;
},
ts =>
{
var a = ts.Alias;
return(a.IsNullOrEmpty() ? "t1" : a + (a.EndsWith("_") ? string.Empty : "_") + "1");
},
StringComparer.OrdinalIgnoreCase);
Utils.MakeUniqueNames(Parameters,
n => !allAliases.Contains(n) && !ReservedWords.IsReserved(n), p => p.Name, (p, n) =>
{
allAliases.Add(n);
p.Name = n;
},
ts => ts.Name ?? "p1",
StringComparer.OrdinalIgnoreCase);
_aliases = allAliases;
}
