* first set of #40051, up to db.pp

* reverted change to a virtual method.

* second batch up to sqlscript

* up to sqldblib, skipping dbase/ (which is shortstring based)

packages/fcl-db/src/base/bufdataset.pas

@@ -558,7 +558,7 @@ type
     function GetIndexFieldNames: String;
     function GetIndexName: String;
     procedure SetIndexFieldNames(const AValue: String);
-    procedure SetIndexName(AValue: String);
+    procedure SetIndexName(const AValue: String);
     procedure SetMaxIndexesCount(const AValue: Integer);
     procedure SetBufUniDirectional(const AValue: boolean);
     Function DefaultIndex : TBufDatasetIndex;
@@ -2399,7 +2399,7 @@ begin
   FPacketRecords:=-1;
 end;
 
-procedure TCustomBufDataset.SetIndexName(AValue: String);
+procedure TCustomBufDataset.SetIndexName(const AValue: String);
 
 var
   F : TBufDatasetIndex;

packages/fcl-db/src/base/bufdataset_parser.pp

@@ -45,7 +45,7 @@ type
 
     procedure FillExpressList; override;
     procedure HandleUnknownVariable(VarName: string); override;
-    function  GetVariableInfo(VarName: string): TField;
+    function  GetVariableInfo(const VarName: string): TField;
     function  CurrentExpression: string; override;
     function  GetResultType: TExpressionType; override;
 
@@ -394,7 +394,7 @@ begin
     ParseExpression(lExpression);
 end;
 
-function TBufDatasetParser.GetVariableInfo(VarName: string): TField;
+function TBufDatasetParser.GetVariableInfo(const VarName: string): TField;
 begin
   Result := FDataset.FindField(VarName);
 end;

packages/fcl-db/src/base/csvdataset.pp

@@ -111,7 +111,7 @@ Type
     procedure LoadFromCSVStream(AStream : TStream);
     procedure LoadFromCSVFile(Const AFileName: string);
     procedure SaveToCSVStream(AStream : TStream);
-    procedure SaveToCSVFile(AFileName: string = '');
+    procedure SaveToCSVFile(const AFileName: string = '');
   Protected
     Property CSVOptions : TCSVOptions Read FCSVOptions Write SetCSVOptions;
   end;
@@ -411,7 +411,7 @@ begin
   end;
 end;
 
-procedure TCustomCSVDataset.SaveToCSVFile(AFileName: string);
+procedure TCustomCSVDataset.SaveToCSVFile(const AFileName: string);
 Var
   F : TFileStream;
 

packages/fcl-db/src/base/db.pas

@@ -1534,11 +1534,11 @@ type
     Function  IsEqual(Value: TParams): Boolean;
     Function GetEnumerator: TParamsEnumerator;
     Function  ParamByName(const Value: string): TParam;
-    Function  ParseSQL(SQL: String; DoCreate: Boolean): String; overload;
-    Function  ParseSQL(SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle): String; overload;
-    Function  ParseSQL(SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle; out ParamBinding: TParambinding): String; overload;
-    Function  ParseSQL(SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle; out ParamBinding: TParambinding; out ReplaceString : string): String; overload;
-    function  ParseSQL(SQL: String; Options : TSQLParseOptions; ParameterStyle: TParamStyle; out ParamBinding: TParambinding; MacroChar: Char; out ReplaceString: string): String;
+    Function  ParseSQL(const SQL: String; DoCreate: Boolean): String; overload;
+    Function  ParseSQL(const SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle): String; overload;
+    Function  ParseSQL(const SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle; out ParamBinding: TParambinding): String; overload;
+    Function  ParseSQL(const SQL: String; DoCreate, EscapeSlash, EscapeRepeat : Boolean; ParameterStyle : TParamStyle; out ParamBinding: TParambinding; out ReplaceString : string): String; overload;
+    function  ParseSQL(const SQL: String; Options : TSQLParseOptions; ParameterStyle: TParamStyle; out ParamBinding: TParambinding; MacroChar: Char; out ReplaceString: string): String;
     Procedure RemoveParam(Value: TParam);
     Procedure CopyParamValuesFromDataset(ADataset : TDataset; CopyBound : Boolean);
     Property Dataset : TDataset Read GetDataset;

packages/fcl-db/src/base/dbcoll.pp

@@ -31,14 +31,14 @@ type
   private
     FDataset: TDataset;
   Protected
-    Function FindField(FN : String) : TField;
-    Function FieldByName(FN : String) : TField;
+    Function FindField(const FN : String) : TField;
+    Function FieldByName(const FN : String) : TField;
   Public
     Constructor Create(ADataset : TDataset); virtual;
     Procedure InitFields; virtual; abstract;
     Procedure LoadObject(AObject: TObject); virtual; abstract;
     Function GetFromField(F : TField; ADefault : Integer) : Integer; overload;
-    Function GetFromField(F : TField; ADefault : String) : String; overload;
+    Function GetFromField(F : TField; const ADefault : String) : String; overload;
     Function GetFromField(F : TField; ADefault : Boolean) : Boolean; overload;
     Function GetFromField(F : TField; ADefault : TDateTime) : TDateTime; overload;
     Function GetFromField(F : TField; ADefault : Double) : Double; overload;
@@ -82,7 +82,7 @@ begin
   InitFields;
 end;
 
-function TFieldMap.FieldByName(FN: String): TField;
+function TFieldMap.FieldByName(const FN: String): TField;
 begin
   If (FDataset=Nil) then
     begin
@@ -93,7 +93,7 @@ begin
     Result:=FDataset.FieldByName(FN);
 end;
 
-function TFieldMap.FindField(FN: String): TField;
+function TFieldMap.FindField(const FN: String): TField;
 begin
   If (FDataset=Nil) then
     Result:=Nil
@@ -109,7 +109,7 @@ begin
     Result:=ADefault;
 end;
 
-function TFieldMap.GetFromField(F: TField; ADefault: String): String;
+function TFieldMap.GetFromField(F: TField; const ADefault: String): String;
 begin
   If Assigned(F) then
     Result:=F.AsString

packages/fcl-db/src/base/dbwhtml.pp

@@ -82,8 +82,8 @@ Type
     function GetColumn(Index : Integer): TTableColumn;
     procedure SetColumn(Index : Integer; const AValue: TTableColumn);
   Public
-    Function FindColumn(ColumnName : String) : TTableColumn;
-    Function ColumnByName(ColumnName : String) : TTableColumn;
+    Function FindColumn(const ColumnName : String) : TTableColumn;
+    Function ColumnByName(const ColumnName : String) : TTableColumn;
     Property Items[Index : Integer] : TTableColumn Read GetColumn Write SetColumn;
   end;
 
@@ -130,10 +130,10 @@ Type
   Public
     Constructor Create(AOwner : TComponent); override;
     Destructor Destroy; virtual;
-    Function CreateAttr(Const ABGColor : String; A : THTMLAlign; VA : THTMLVAlign; CustomAttr : String) : String;
+    Function CreateAttr(Const ABGColor : String; A : THTMLAlign; VA : THTMLVAlign; const CustomAttr : String) : String;
     Procedure Clear;
     Procedure CreateColumns(FieldList : TStrings);
-    Procedure CreateColumns(FieldList : String);
+    Procedure CreateColumns(const FieldList : String);
     Procedure CreateTable(Stream : TStream);
     Procedure CreateTable;
     Procedure CreateContent; override;
@@ -201,7 +201,7 @@ begin
   Inherited Items[Index]:=AValue;
 end;
 
-function TTableColumns.FindColumn(ColumnName: String): TTableColumn;
+function TTableColumns.FindColumn(const ColumnName: String): TTableColumn;
 
 Var
   I : Integer;
@@ -215,7 +215,7 @@ begin
     Result:=Items[I];
 end;
 
-function TTableColumns.ColumnByName(ColumnName: String): TTableColumn;
+function TTableColumns.ColumnByName(const ColumnName: String): TTableColumn;
 
 begin
   Result:=FindColumn(ColumnName);
@@ -343,7 +343,7 @@ begin
   WriteString(Stream,'</TABLE>'#10);
 end;
 
-Function TTableProducer.CreateAttr(Const ABGColor : String; A : THTMLAlign; VA : THTMLVAlign; CustomAttr : String) : String;
+Function TTableProducer.CreateAttr(Const ABGColor : String; A : THTMLAlign; VA : THTMLVAlign; const CustomAttr : String) : String;
 
 Const
   HAligns : Array[THTMLAlign] of string = ('','"left"','"right"','"center"');
@@ -447,7 +447,7 @@ begin
     end
 end;
 
-procedure TTableProducer.CreateColumns(FieldList: String);
+procedure TTableProducer.CreateColumns(const FieldList: String);
 
 Var
   L : TStringList;

packages/fcl-db/src/base/dsparams.inc

@@ -229,7 +229,7 @@ begin
     DatabaseErrorFmt(SParameterNotFound,[Value],Dataset);
 end;
 
-function TParams.ParseSQL(SQL: String; DoCreate: Boolean): String;
+function TParams.ParseSQL(const SQL: String; DoCreate: Boolean): String;
 
 var
   pb : TParamBinding;
@@ -241,7 +241,7 @@ begin
   Result := DoParseSQL(SQL,PO,psInterbase, pb, ' ',rs);
 end;
 
-function TParams.ParseSQL(SQL: String; DoCreate, EscapeSlash,
+function TParams.ParseSQL(const SQL: String; DoCreate, EscapeSlash,
   EscapeRepeat: Boolean; ParameterStyle: TParamStyle): String;
 
 var pb : TParamBinding;
@@ -253,7 +253,7 @@ begin
   Result := DoParseSQL(SQL,PO,ParameterStyle,pb,' ',rs);
 end;
 
-function TParams.ParseSQL(SQL: String; DoCreate, EscapeSlash,
+function TParams.ParseSQL(const SQL: String; DoCreate, EscapeSlash,
   EscapeRepeat: Boolean; ParameterStyle: TParamStyle; out
   ParamBinding: TParambinding): String;
 
@@ -313,7 +313,7 @@ begin
 end;
 
 
-function TParams.ParseSQL(SQL: String; DoCreate, EscapeSlash,
+function TParams.ParseSQL(const SQL: String; DoCreate, EscapeSlash,
   EscapeRepeat: Boolean; ParameterStyle: TParamStyle; out
   ParamBinding: TParambinding; out ReplaceString: string): String;
 
@@ -325,7 +325,7 @@ begin
   Result:=DoParseSQL(SQL,PO,ParameterStyle,ParamBinding,' ',ReplaceString);
 end;
 
-function TParams.ParseSQL(SQL: String; Options: TSQLParseOptions; ParameterStyle: TParamStyle; out ParamBinding: TParambinding;
+function TParams.ParseSQL(const SQL: String; Options: TSQLParseOptions; ParameterStyle: TParamStyle; out ParamBinding: TParambinding;
   MacroChar: Char; out ReplaceString: string): String;
 begin
   Result:=DoParseSQL(SQL,Options,ParameterStyle,ParamBinding,MacroChar,ReplaceString);

packages/fcl-db/src/base/fieldmap.pp

@@ -37,8 +37,8 @@ type
     FOldOnOpen : TDataSetNotifyEvent;
   Protected
     Procedure DoOnOpen(Sender : TDataset);
-    Function FindField(FN : String) : TField;
-    Function FieldByName(FN : String) : TField;
+    Function FindField(const FN : String) : TField;
+    Function FieldByName(const FN : String) : TField;
   Public
     Constructor Create(ADataset : TDataset; HookOnOpen : Boolean = False);
     Destructor Destroy; override;
@@ -46,7 +46,7 @@ type
     Procedure LoadObject(AObject : TObject); virtual;
     Function GetFromField(F : TField; ADefault : TBCD) : TBCD; overload;
     Function GetFromField(F : TField; ADefault : Integer) : Integer; overload;
-    Function GetFromField(F : TField; ADefault : String) : String; overload;
+    Function GetFromField(F : TField; const ADefault : String) : String; overload;
     Function GetFromField(F : TField; ADefault : Boolean) : Boolean; overload;
     Function GetFromDateTimeField(F : TField; ADefault : TDateTime) : TDateTime; overload;
     Function GetFromField(F : TField; ADefault : Double) : Double; overload;
@@ -54,8 +54,8 @@ type
     Function GetFromField(F : TField; ADefault : Int64) : Int64; overload;
     Function GetFromField(F : TField; ADefault : LongWord) : LongWord; overload;
     Function GetFromField(F : TField; ADefault : Currency) : Currency; overload;
-    Function GetFromField(F : TField; ADefault : UnicodeString) : UnicodeString; overload;
-    Function GetFromField(F : TField; ADefault : WideString) : WideString; overload;
+    Function GetFromField(F : TField; const ADefault : UnicodeString) : UnicodeString; overload;
+    Function GetFromField(F : TField; const ADefault : WideString) : WideString; overload;
     Function GetFromField(F : TField; ADefault : TBytes) : TBytes; overload;
     Property Dataset : TDataset Read FDataset;
     Property FreeDataset : Boolean Read FFreeDataset Write FFreeDataset;
@@ -68,8 +68,8 @@ type
   private
     FParams: TParams;
   Protected
-    Function FindParam(FN : String) : TParam;
-    Function ParamByName(FN : String) : TParam;
+    Function FindParam(const FN : String) : TParam;
+    Function ParamByName(const FN : String) : TParam;
   Public
     Constructor Create(AParams : TParams);
     Procedure InitParams; virtual; abstract;
@@ -468,14 +468,14 @@ end;
 
 { TParamMap }
 
-function TParamMap.FindParam(FN: String): TParam;
+function TParamMap.FindParam(const FN: String): TParam;
 begin
   Result:=FParams.FindParam(FN);
   {if (Result=Nil) then
     Writeln(ClassName,' param ',FN,' not found');}
 end;
 
-function TParamMap.ParamByName(FN: String): TParam;
+function TParamMap.ParamByName(const FN: String): TParam;
 begin
   If (FParams=Nil) then
     Raise Exception.CreateFmt(SErrNoParamsForParam,[ClassName,FN]);
@@ -525,7 +525,7 @@ begin
       Result:=ADefault;
 end;
 
-function TFieldMap.FieldByName(FN: String): TField;
+function TFieldMap.FieldByName(const FN: String): TField;
 begin
   Result:=FDataset.FieldByName(FN)
 end;
@@ -537,7 +537,7 @@ begin
     FOldOnOpen(Sender);
 end;
 
-function TFieldMap.FindField(FN: String): TField;
+function TFieldMap.FindField(const FN: String): TField;
 begin
   If (FDataset=Nil) then
     Result:=Nil
@@ -553,7 +553,7 @@ begin
     Result:=ADefault;
 end;
 
-function TFieldMap.GetFromField(F: TField; ADefault: String): String;
+function TFieldMap.GetFromField(F: TField; const ADefault: String): String;
 begin
   If Assigned(F) then
     Result:=F.AsString
@@ -625,7 +625,7 @@ begin
     Result:=ADefault;
 end;
 
-function TFieldMap.GetFromField(F: TField; ADefault: UnicodeString): UnicodeString;
+function TFieldMap.GetFromField(F: TField; const ADefault: UnicodeString): UnicodeString;
 begin
   If Assigned(F) then
     Result:=F.AsUnicodeString
@@ -633,7 +633,7 @@ begin
     Result:=ADefault;
 end;
 
-function TFieldMap.GetFromField(F: TField; ADefault: WideString): WideString;
+function TFieldMap.GetFromField(F: TField; const ADefault: WideString): WideString;
 begin
   If Assigned(F) then
     Result:=F.AsWideString

packages/fcl-db/src/base/sqlscript.pp

@@ -189,7 +189,7 @@ begin
     end;
 end;
 
-Function ConvertWhiteSpace(S : String) : String;
+Function ConvertWhiteSpace(const S : String) : String;
 
 begin
   Result:=StringReplace(S,#13,' ',[rfReplaceAll]);
@@ -645,7 +645,7 @@ end;
 
 procedure TCustomSQLScript.DefaultDirectives;
 
-  Procedure Add(S : String);
+  Procedure Add(const S : String);
   
   begin
     if FDirectives.IndexOf(S)=-1 then

packages/fcl-db/src/base/xmldatapacketreader.pp

@@ -132,7 +132,7 @@ end;
 
 procedure TXMLDatapacketReader.LoadFieldDefs(var AnAutoIncValue: integer);
 
-  function GetNodeAttribute(const aNode : TDOMNode; AttName : String) : string;
+  function GetNodeAttribute(const aNode : TDOMNode; const AttName : String) : string;
   var AnAttr : TDomNode;
   begin
     AnAttr := ANode.Attributes.GetNamedItem(AttName);

packages/fcl-db/src/codegen/fpcgtiopf.pp

@@ -133,7 +133,7 @@ Const
   
 implementation
 
-Function StripType(S : String) : string;
+Function StripType(const S : String) : string;
 
 begin
   Result:=S;

packages/fcl-db/src/codegen/fpcgtypesafedataset.pp

@@ -56,8 +56,8 @@ Type
     function GetInterfaceName: String;
     function GetQueryClass: String;
     function GetTransactionClass: String;
-    procedure SetInterfaceGUID(AValue: String);
-    procedure SetInterfaceName(AValue: String);
+    procedure SetInterfaceGUID(const AValue: String);
+    procedure SetInterfaceName(const AValue: String);
     procedure SetTypeSafeAccesOptions(AValue: TTypeSafeDatasetOptions);
   Protected
     function GetMapAncestorName: String; override;
@@ -891,7 +891,7 @@ begin
     Result:='TSQLConnection';
 end;
 
-procedure TGenTypeSafeDatasetOptions.SetInterfaceGUID(AValue: String);
+procedure TGenTypeSafeDatasetOptions.SetInterfaceGUID(const AValue: String);
 
 Var
   G : TGUID;
@@ -901,7 +901,7 @@ begin
   FInterfaceGUID:=GUIDToString(G);
 end;
 
-procedure TGenTypeSafeDatasetOptions.SetInterfaceName(AValue: String);
+procedure TGenTypeSafeDatasetOptions.SetInterfaceName(const AValue: String);
 begin
   CheckIdentifier(AValue,True);
   FInterfaceName:=AValue;

packages/fcl-db/src/codegen/fpddcodegen.pp

@@ -95,13 +95,13 @@ Type
     function GetPropDef(Index : integer): TFieldPropDef;
     procedure SetPropDef(Index : integer; const AValue: TFieldPropDef);
   Public
-    Function AddDef(AName : String) : TFieldPropDef;
+    Function AddDef(const AName : String) : TFieldPropDef;
     Procedure FromDataset(Dataset : TDataset; DoClear : Boolean = True);
     Procedure FromDDFieldDefs(Defs : TDDFieldDefs; DoClear : Boolean = True);
-    Function IndexOfPropName(AName : String) : Integer;
-    Function IndexOfFieldName(AName : String) : Integer;
-    Function FindPropName(AName : String) : TFieldPropDef;
-    Function FindFieldName(AName : String) : TFieldPropDef;
+    Function IndexOfPropName(const AName : String) : Integer;
+    Function IndexOfFieldName(const AName : String) : Integer;
+    Function FindPropName(const AName : String) : TFieldPropDef;
+    Function FindFieldName(const AName : String) : TFieldPropDef;
     Property PropDefs[Index : integer] : TFieldPropDef Read GetPropDef write SetPropDef; Default;
   end;
 
@@ -152,10 +152,10 @@ Type
   Protected
     // Utility routines to add lines to the code. Will prepend indent.
     procedure AddLn(Strings: TStrings); overload;
-    procedure AddLn(Strings: TStrings; Line: String); overload;
-    procedure AddLn(Strings: TStrings; Fmt: String; Args: array of const); overload;
+    procedure AddLn(Strings: TStrings; const Line: String); overload;
+    procedure AddLn(Strings: TStrings; const Fmt: String; Args: array of const); overload;
     // Create a pascal code string. Surround by quotes or not
-    Function CreatePascalString(S : String; Quote : Boolean = True) : String;
+    Function CreatePascalString(const S : String; Quote : Boolean = True) : String;
     // Increase indent by defined amount
     procedure IncIndent;
     // Decrease indent by defined amount
@@ -442,20 +442,20 @@ Resourcestring
   SErrGeneratorExists   = 'A code generator with name "%s" already exists';
   SUnknownGenerator     = 'Unknown code generator name : "%s"';
 
-Function MakeIdentifier (S : String) : String;
-Function CreateString(S : String) : String;
-Procedure CheckIdentifier(AValue : String; AllowEmpty : Boolean = True);
+Function MakeIdentifier (const S : String) : String;
+Function CreateString(const S : String) : String;
+Procedure CheckIdentifier(const AValue : String; AllowEmpty : Boolean = True);
 
 implementation
 
-Function CreateString(S : String) : String;
+Function CreateString(const S : String) : String;
 
 begin
   Result:=StringReplace(S,'''','''''',[rfReplaceAll]);
   Result:=''''+Result+'''';
 end;
 
-Procedure CheckIdentifier(AValue : String; AllowEmpty : Boolean = True);
+Procedure CheckIdentifier(const AValue : String; AllowEmpty : Boolean = True);
 
 begin
   If ((AValue='') and Not AllowEmpty) or Not IsValidIdent(AValue) then
@@ -494,7 +494,7 @@ begin
   CodeGenerators.UnRegisterCodeGenerator(AName);
 end;
 
-Function MakeIdentifier (S : String) : String;
+Function MakeIdentifier (const S : String) : String;
 
 Var
   I : Integer;
@@ -642,7 +642,7 @@ begin
   Items[Index]:=AValue;
 end;
 
-function TFieldPropDefs.AddDef(AName: String): TFieldPropDef;
+function TFieldPropDefs.AddDef(const AName: String): TFieldPropDef;
 begin
   Result:=Add As TFieldPropDef;
   Result.FieldName:=AName;
@@ -686,21 +686,21 @@ begin
     end;
 end;
 
-function TFieldPropDefs.IndexOfPropName(AName: String): Integer;
+function TFieldPropDefs.IndexOfPropName(const AName: String): Integer;
 begin
   Result:=Count-1;
   While (Result>=0) and (CompareText(GetPropDef(Result).PropertyName,AName)<>0) do
     Dec(Result);
 end;
 
-function TFieldPropDefs.IndexOfFieldName(AName: String): Integer;
+function TFieldPropDefs.IndexOfFieldName(const AName: String): Integer;
 begin
   Result:=Count-1;
   While (Result>=0) and (CompareText(GetPropDef(Result).FieldName,AName)<>0) do
     Dec(Result);
 end;
 
-function TFieldPropDefs.FindPropName(AName: String): TFieldPropDef;
+function TFieldPropDefs.FindPropName(const AName: String): TFieldPropDef;
 
 Var
   I : Integer;
@@ -713,7 +713,7 @@ begin
     Result:=Nil;
 end;
 
-function TFieldPropDefs.FindFieldName(AName: String): TFieldPropDef;
+function TFieldPropDefs.FindFieldName(const AName: String): TFieldPropDef;
 
 Var
   I : Integer;
@@ -1389,20 +1389,20 @@ begin
   Strings.Add('');
 end;
 
-procedure TDDCustomCodeGenerator.AddLn(Strings : TStrings; Line : String);
+procedure TDDCustomCodeGenerator.AddLn(Strings : TStrings; const Line : String);
 
 begin
   Strings.Add(FCurrentIndent+Line);
 end;
 
-procedure TDDCustomCodeGenerator.AddLn(Strings: TStrings; Fmt: String;
+procedure TDDCustomCodeGenerator.AddLn(Strings: TStrings; const Fmt: String;
   Args: array of const);
 
 begin
   Strings.Add(FCurrentIndent+Format(Fmt,Args));
 end;
 
-function TDDCustomCodeGenerator.CreatePascalString(S: String; Quote: Boolean): String;
+function TDDCustomCodeGenerator.CreatePascalString(const S: String; Quote: Boolean): String;
 
 Var
   SW : String;

packages/fcl-db/src/export/fpdbexport.pp

@@ -175,8 +175,8 @@ Type
     // Format field as UTF8 string, according to settings
     Function FormatField(F : TField) : UTF8String; virtual;
     // Raise EDataExporter error
-    Procedure ExportError(Msg : String); overload;
-    Procedure ExportError(Fmt : String; Args: Array of const); overload;
+    Procedure ExportError(const Msg : String); overload;
+    Procedure ExportError(const Fmt : String; Args: Array of const); overload;
   Public
     Constructor Create(AOwner : TComponent); override;
     Destructor Destroy; override;
@@ -674,12 +674,12 @@ begin
     Result:=F.AsUTF8String;
 end;
 
-procedure TCustomDatasetExporter.ExportError(Msg: String);
+procedure TCustomDatasetExporter.ExportError(const Msg: String);
 begin
   Raise EDataExporter.Create(Msg);
 end;
 
-procedure TCustomDatasetExporter.ExportError(Fmt: String;
+procedure TCustomDatasetExporter.ExportError(const Fmt: String;
   Args: array of const);
 begin
   Raise EDataExporter.CreateFmt(Fmt,Args);
@@ -992,7 +992,7 @@ end;
 function TExportFormats.ConstructFilter(AnExport: TCustomDatasetExporter
   ): String;
   
-  Procedure AddToResult(S : String);
+  Procedure AddToResult(const S : String);
   
   begin
     If (Result<>'') and (S<>'') then

packages/fcl-db/src/export/fpsimplejsonexport.pp

@@ -58,7 +58,7 @@ Type
     procedure IncIndent;
     procedure OutputRow(const ARow: String);
     procedure SetJSONFormatSettings(const AValue: TSimpleJSONFormatSettings);
-    function TextString(S: String): String;
+    function TextString(const S: String): String;
   Protected
     Function  CreateFormatSettings : TCustomExportFormatSettings; override;
     Procedure DoBeforeExecute; override;
@@ -145,7 +145,7 @@ begin
   Inherited FormatSettings.Assign(AValue);
 end;
 
-function TCustomSimpleJSONExporter.TextString(S: String): String;
+function TCustomSimpleJSONExporter.TextString(const S: String): String;
 
 Var
   I,J,L : Integer;

packages/fcl-db/src/export/fptexexport.pp

@@ -72,7 +72,7 @@ Type
     function GetTeXFormatsettings: TTexExportFormatSettings;
     procedure SetTeXFormatSettings(const AValue: TTexExportFormatSettings);
   Protected
-    function EscapeLaTeX(S: String): String;
+    function EscapeLaTeX(const S: String): String;
     procedure OutputRow(const ARow: String); virtual;
     procedure OutputTableEnd; virtual;
     procedure OutputTableStart; virtual;
@@ -132,7 +132,7 @@ begin
 end;
 
 { TCustomTeXExporter }
-function TCustomTexExporter.EscapeLaTeX(S: String): String;
+function TCustomTexExporter.EscapeLaTeX(const S: String): String;
 
 Var
   I,J,L : Integer;

packages/fcl-db/src/json/fpjsondataset.pp

@@ -193,7 +193,7 @@ type
     function DataTypeToComparerClass(aFieldType: TFieldType): TFieldComparerClass;
     Function Compare(aRowindex : integer) : Integer;
   Public
-    Constructor Create(aDataset : TBaseJSONDataset; aFields : String; aValues : Variant; aOptions : TLocateOptions);
+    Constructor Create(aDataset : TBaseJSONDataset; const aFields : String; aValues : Variant; aOptions : TLocateOptions);
     Destructor Destroy; override;
     Property Dataset : TBaseJSONDataset Read FDataset;
     property Items [Index : Integer] : TFieldComparer Read GetFieldComparer;
@@ -533,7 +533,7 @@ begin
     end;
 end;
 
-constructor TRecordComparer.Create(aDataset: TBaseJSONDataset; aFields: String; aValues: Variant; aOptions: TLocateOptions);
+constructor TRecordComparer.Create(aDataset: TBaseJSONDataset; const aFields: String; aValues: Variant; aOptions: TLocateOptions);
 
 Var
   L,H,I : Integer;

packages/fcl-db/src/memds/memds.pp

@@ -116,8 +116,8 @@ type
     function GetRecNo: Integer; override;
 
     // Own.
-    procedure SetFilterText(AValue: string); //silently drops filter
-    Procedure RaiseError(Fmt : String; Args : Array of const);
+    procedure SetFilterText(const AValue: string); //silently drops filter
+    Procedure RaiseError(const Fmt : String; Args : Array of const);
     Procedure CheckMarker(F : TStream; Marker : Integer);
     Procedure WriteMarker(F : TStream; Marker : Integer);
     Procedure ReadFieldDefsFromStream(F : TStream);
@@ -141,12 +141,12 @@ type
     Function  DataSize : Integer;
     Procedure Clear(ClearDefs : Boolean);{$IFNDEF FPC} overload; {$ENDIF}
     Procedure Clear;{$IFNDEF FPC} overload; {$ENDIF}
-    Procedure SaveToFile(AFileName : String);{$IFNDEF FPC} overload; {$ENDIF}
-    Procedure SaveToFile(AFileName : String; SaveData : Boolean);{$IFNDEF FPC} overload; {$ENDIF}
+    Procedure SaveToFile(const AFileName : String);{$IFNDEF FPC} overload; {$ENDIF}
+    Procedure SaveToFile(const AFileName : String; SaveData : Boolean);{$IFNDEF FPC} overload; {$ENDIF}
     Procedure SaveToStream(F : TStream); {$IFNDEF FPC} overload; {$ENDIF}
     Procedure SaveToStream(F : TStream; SaveData : Boolean);{$IFNDEF FPC} overload; {$ENDIF}
     Procedure LoadFromStream(F : TStream);
-    Procedure LoadFromFile(AFileName : String);
+    Procedure LoadFromFile(const AFileName : String);
     Procedure CopyFromDataset(DataSet : TDataSet); {$IFNDEF FPC} overload; {$ENDIF}
     Procedure CopyFromDataset(DataSet : TDataSet; CopyData : Boolean); {$IFNDEF FPC} overload; {$ENDIF}
 
@@ -281,7 +281,7 @@ begin
   S.WriteBuffer(Value,SizeOf(Value));
 end;
 
-Procedure WriteString(S : TStream; Value : String);
+Procedure WriteString(S : TStream; const Value : String);
 
 Var
   L : Integer;
@@ -452,7 +452,7 @@ begin
   Result:= getIntegerPointer(ffieldoffsets, fieldno-1)^;
 end;
 
-procedure TMemDataset.RaiseError(Fmt: String; Args: array of const);
+procedure TMemDataset.RaiseError(const Fmt: String; Args: array of const);
 
 begin
   Raise MDSError.CreateFmt(Fmt,Args);
@@ -705,7 +705,7 @@ begin
   FFileModified:=False;
 end;
 
-procedure TMemDataset.LoadFromFile(AFileName: String);
+procedure TMemDataset.LoadFromFile(const AFileName: String);
 
 Var
   F : TFileStream;
@@ -720,13 +720,13 @@ begin
 end;
 
 
-procedure TMemDataset.SaveToFile(AFileName: String);
+procedure TMemDataset.SaveToFile(const AFileName: String);
 
 begin
   SaveToFile(AFileName,True);
 end;
 
-procedure TMemDataset.SaveToFile(AFileName: String; SaveData: Boolean);
+procedure TMemDataset.SaveToFile(const AFileName: String; SaveData: Boolean);
 
 Var
   F : TFileStream;
@@ -1305,7 +1305,7 @@ begin
   end;
 end;
 
-procedure TMemDataset.SetFilterText(AValue: string);
+procedure TMemDataset.SetFilterText(const AValue: string);
 begin
   // Just do nothing; filter is not implemented
 end;

packages/fcl-db/src/paradox/paradox.pp

@@ -56,7 +56,7 @@ type
     procedure PXAppendRecord(Buffer: Pointer);
     function PXFilterRecord(Buffer: TRecordBuffer): Boolean;
     function PXGetActiveBuffer(var Buffer: TRecordBuffer): Boolean;
-    procedure RaiseError(Fmt: String; Args: array of const);
+    procedure RaiseError(const Fmt: String; Args: array of const);
     procedure SetBlobFileName(const AValue: String);
     procedure SetFileName(const AValue: String);
     procedure SetInputEncoding(const AValue: String);
@@ -225,7 +225,7 @@ begin
     end;
 end;
 
-Procedure InitPXLib(LibName : String);
+Procedure InitPXLib(const LibName : String);
 
 begin
   If (PXLibRefCount=0) then
@@ -256,7 +256,7 @@ begin
 end;
 
 
-Procedure TParadox.RaiseError(Fmt : String; Args : Array of const);
+Procedure TParadox.RaiseError(const Fmt : String; Args : Array of const);
 
 begin
   Raise EParadox.CreateFmt(Fmt,Args);

packages/fcl-db/src/sdf/sdfdata.pp

@@ -167,9 +167,9 @@ type
     FLoadFromStream     :Boolean;
     FTrimSpace          :Boolean;
     FEncoding : TEncoding;
-    procedure SetCodePage(AValue: String);
+    procedure SetCodePage(const AValue: String);
     procedure SetSchema(const Value: TStringList);
-    procedure SetFileName(Value : TFileName);
+    procedure SetFileName(const Value : TFileName);
     procedure SetFileMustExist(Value : Boolean);
     procedure SetTrimSpace(Value : Boolean);
     procedure SetReadOnly(Value : Boolean);
@@ -229,7 +229,7 @@ type
     function  GetFieldData(Field: TField; Buffer: Pointer): Boolean; override;
     procedure RemoveBlankRecords; dynamic;
     procedure RemoveExtraColumns; dynamic;
-    procedure SaveFileAs(strFileName : String); dynamic;
+    procedure SaveFileAs(const strFileName : String); dynamic;
     property  CanModify;
     procedure LoadFromStream(Stream :TStream);
     procedure SaveToStream(Stream :TStream);
@@ -338,7 +338,7 @@ begin
   FSchema.Assign(Value);
 end;
 
-procedure TFixedFormatDataSet.SetCodePage(AValue: String);
+procedure TFixedFormatDataSet.SetCodePage(const AValue: String);
 
 Var
   F : TSystemCodePage;
@@ -372,7 +372,7 @@ begin
   FReadOnly := Value;
 end;
 
-procedure TFixedFormatDataSet.SetFileName(Value : TFileName);
+procedure TFixedFormatDataSet.SetFileName(const Value : TFileName);
 begin
   CheckInactive;
   FFileName := Value;
@@ -899,7 +899,7 @@ begin
   FData.SaveToFile(FileName);
 end;
 
-procedure TFixedFormatDataSet.SaveFileAs(strFileName : String);
+procedure TFixedFormatDataSet.SaveFileAs(const strFileName : String);
 begin
   FData.SaveToFile(strFileName);
   FFileName := strFileName;

packages/fcl-db/src/sql/fpsqlparser.pas

@@ -71,8 +71,8 @@ Type
     procedure Consume(aToken: TSQLToken);
     // Expects aTokens tokens and eats the token by calling GetNextToken
     procedure Consume(aTokens: TSQLTokens);
-    procedure Error(Msg : String);
-    procedure Error(Fmt : String; Args : Array of const);
+    procedure Error(const Msg : String);
+    procedure Error(const Fmt : String; Args : Array of const);
     // Expression support
     function ParseExprLevel1(AParent: TSQLElement; EO : TExpressionOptions): TSQLExpression;
     function ParseExprLevel2(AParent: TSQLElement; EO : TExpressionOptions): TSQLExpression;
@@ -299,7 +299,7 @@ begin
   Result:=FScanner.CurColumn;
 end;
 
-procedure TSQLParser.Error(Msg: String);
+procedure TSQLParser.Error(const Msg: String);
 
 Var
   ErrAt : String;
@@ -321,7 +321,7 @@ begin
    Raise E;
 end;
 
-procedure TSQLParser.Error(Fmt: String; Args: array of const);
+procedure TSQLParser.Error(const Fmt: String; Args: array of const);
 begin
   Error(Format(Fmt,Args));
 end;

packages/fcl-db/src/sql/fpsqltree.pp

@@ -4049,7 +4049,7 @@ begin
 end;
 
 
-Function SQLIndentStatement(S : String; Options: TSQLFormatOptions) : String;
+Function SQLIndentStatement(const S : String; Options: TSQLFormatOptions) : String;
 
 Var
   L : TStringList;

packages/fcl-db/src/sqldb/sqldblib.pp

@@ -31,9 +31,9 @@ Type
     FEnabled: Boolean;
     FLibraryName: String;
     procedure CheckDisabled;
-    procedure SetCType(AValue: String);
+    procedure SetCType(const AValue: String);
     procedure SetEnabled(AValue: Boolean);
-    procedure SetLibraryName(AValue: String);
+    procedure SetLibraryName(const AValue: String);
   Protected
     Function GetConnectionDef : TConnectionDef;
     Procedure Loaded; override;
@@ -61,7 +61,7 @@ begin
     DatabaseError(SErrConnnected,Self);
 end;
 
-procedure TSQLDBLibraryLoader.SetCType(AValue: String);
+procedure TSQLDBLibraryLoader.SetCType(const AValue: String);
 begin
   if FCType=AValue then Exit;
   CheckDisabled;
@@ -82,7 +82,7 @@ begin
       UnloadLibrary;
 end;
 
-procedure TSQLDBLibraryLoader.SetLibraryName(AValue: String);
+procedure TSQLDBLibraryLoader.SetLibraryName(const AValue: String);
 begin
   if FLibraryName=AValue then Exit;
   CheckDisabled;