fbintf/client/FBStatement.pas

(*
 *  Firebird Interface (fbintf). The fbintf components provide a set of
 *  Pascal language bindings for the Firebird API. Although predominantly
 *  a new development they include source code taken from IBX and may be
 *  considered a derived product. This software thus also includes the copyright
 *  notice and license conditions from IBX.
 *
 *  Except for those parts dervied from IBX, contents of this file are subject
 *  to the Initial Developer's Public License Version 1.0 (the "License"); you
 *  may not use this file except in compliance with the License. You may obtain a
 *  copy of the License here:
 *
 *    http://www.firebirdsql.org/index.php?op=doc&id=idpl
 *
 *  Software distributed under the License is distributed on an "AS
 *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 *  implied. See the License for the specific language governing rights
 *  and limitations under the License.
 *
 *  The Initial Developer of the Original Code is Tony Whyman.
 *
 *  The Original Code is (C) 2016 Tony Whyman, MWA Software
 *  (http://www.mwasoftware.co.uk).
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): ______________________________________.
 *
*)
unit FBStatement;
{$IFDEF MSWINDOWS} 
{$DEFINE WINDOWS} 
{$ENDIF}

{$IFDEF FPC}
{$mode delphi}
{$codepage UTF8}
{$interfaces COM}
{$ENDIF}

interface

uses
  Classes, SysUtils,  IB,  FBClientAPI, FBSQLData, FBOutputBlock, FBActivityMonitor,
  FBTransaction;

type
  TPerfStatistics = array[psCurrentMemory..psFetches] of Int64;

  { TFBStatement }

  TFBStatement = class(TActivityReporter)
  private
    FAttachmentIntf: IAttachment;
    FFirebirdClientAPI: TFBClientAPI;
  protected
    FTransactionIntf: ITransaction;
    FExecTransactionIntf: ITransaction;
    FSQLStatementType: TIBSQLStatementTypes;         { Select, update, delete, insert, create, alter, etc...}
    FSQLDialect: integer;
    FOpen: boolean;
    FPrepared: boolean;
    FPrepareSeqNo: integer; {used to check for out of date references from interfaces}
    FSQL: AnsiString;
    FProcessedSQL: AnsiString;
    FHasParamNames: boolean;
    FBOF: boolean;
    FEOF: boolean;
    FSingleResults: boolean;
    FGenerateParamNames: boolean;
    FChangeSeqNo: integer;
    FCollectStatistics: boolean;
    FStatisticsAvailable: boolean;
    FBeforeStats: TPerfStatistics;
    FAfterStats: TPerfStatistics;
    procedure CheckHandle; virtual; abstract;
    procedure CheckTransaction(aTransaction: ITransaction);
    procedure GetDsqlInfo(info_request: byte; buffer: ISQLInfoResults); overload; virtual; abstract;
    procedure InternalPrepare;  virtual; abstract;
    function InternalExecute(aTransaction: ITransaction): IResults;  virtual; abstract;
    function InternalOpenCursor(aTransaction: ITransaction): IResultSet;   virtual; abstract;
    procedure ProcessSQL(sql: AnsiString; GenerateParamNames: boolean; var processedSQL: AnsiString); virtual; abstract;
    procedure FreeHandle;  virtual; abstract;
    procedure InternalClose(Force: boolean); virtual; abstract;
    function TimeStampToMSecs(const TimeStamp: TTimeStamp): Int64;
  public
    constructor Create(Attachment: IAttachment; Transaction: ITransaction;
      sql: AnsiString; SQLDialect: integer);
    constructor CreateWithParameterNames(Attachment: IAttachment; Transaction: ITransaction;
      sql: AnsiString;  SQLDialect: integer; GenerateParamNames: boolean =false);
    destructor Destroy; override;
    procedure Close;
    procedure TransactionEnding(aTransaction: ITransaction; Force: boolean);
    property SQLDialect: integer read FSQLDialect;
    property FirebirdClientAPI: TFBClientAPI read FFirebirdClientAPI;

  public
    function GetSQLParams: ISQLParams; virtual; abstract;
    function GetMetaData: IMetaData;  virtual; abstract;
    function GetRowsAffected(var SelectCount, InsertCount, UpdateCount,
      DeleteCount: integer): boolean;
    function GetSQLStatementType: TIBSQLStatementTypes;
    function GetSQLText: AnsiString;
    function GetProcessedSQLText: AnsiString;
    function GetSQLDialect: integer;

    {GetDSQLInfo only supports isc_info_sql_stmt_type, isc_info_sql_get_plan, isc_info_sql_records}
    procedure Prepare(aTransaction: ITransaction=nil); virtual;
    function Execute(aTransaction: ITransaction=nil): IResults;
    function OpenCursor(aTransaction: ITransaction=nil): IResultSet;
    function CreateBlob(paramName: AnsiString): IBlob; overload;
    function CreateBlob(index: integer): IBlob; overload;
    function CreateBlob(column: TColumnMetaData): IBlob; overload; virtual; abstract;
    function CreateArray(paramName: AnsiString): IArray; overload;
    function CreateArray(index: integer): IArray;  overload;
    function CreateArray(column: TColumnMetaData): IArray; overload; virtual; abstract;
    function GetAttachment: IAttachment;
    function GetTransaction: ITransaction;
    function GetDSQLInfo(Request: byte): ISQLInfoResults; overload;
    procedure SetRetainInterfaces(aValue: boolean); virtual;
    procedure EnableStatistics(aValue: boolean);
    function GetPerfStatistics(var stats: TPerfCounters): boolean;
    property ChangeSeqNo: integer read FChangeSeqNo;
    property SQLParams: ISQLParams read GetSQLParams;
    property SQLStatementType: TIBSQLStatementTypes read GetSQLStatementType;
end;

implementation

uses FBMessages;

{ TFBStatement }

procedure TFBStatement.CheckTransaction(aTransaction: ITransaction);
begin
  if (aTransaction = nil) then
    IBError(ibxeTransactionNotAssigned,[]);

  if not aTransaction.InTransaction then
    IBError(ibxeNotInTransaction,[]);
end;

function TFBStatement.TimeStampToMSecs(const TimeStamp: TTimeStamp): Int64;
begin
  Result := TimeStamp.Time + Int64(timestamp.date)*msecsperday;
end;

constructor TFBStatement.Create(Attachment: IAttachment;
  Transaction: ITransaction; sql: AnsiString; SQLDialect: integer);
begin
  inherited Create(Transaction as TFBTransaction,2);
  FAttachmentIntf := Attachment;
  FTransactionIntf := Transaction;
  FFirebirdClientAPI := Attachment.getFirebirdAPI as TFBClientAPI;
  FSQLDialect := SQLDialect;
  FSQL := sql;
end;

constructor TFBStatement.CreateWithParameterNames(Attachment: IAttachment;
  Transaction: ITransaction; sql: AnsiString; SQLDialect: integer;
  GenerateParamNames: boolean);
begin
  FHasParamNames := true;
  FGenerateParamNames := GenerateParamNames;
  Create(Attachment,Transaction,sql,SQLDialect);
end;

destructor TFBStatement.Destroy;
begin
  Close;
  FreeHandle;
  inherited Destroy;
end;

procedure TFBStatement.Close;
begin
  InternalClose(false);
end;

procedure TFBStatement.TransactionEnding(aTransaction: ITransaction;
  Force: boolean);
begin
  if FOpen and (FExecTransactionIntf = aTransaction) then
    InternalClose(Force);

  if FTransactionIntf = aTransaction then
  begin
    FreeHandle;
    FPrepared := false;
  end;
end;

function TFBStatement.GetRowsAffected(var SelectCount, InsertCount,
  UpdateCount, DeleteCount: integer): boolean;
var
  RB: ISQLInfoResults;
  i, j: integer;
begin
  InsertCount := 0;
  UpdateCount := 0;
  DeleteCount := 0;
  Result := FPrepared;
  if not Result then Exit;

  RB := GetDsqlInfo(isc_info_sql_records);

  for i := 0 to RB.Count - 1 do
  with RB[i] do
  case getItemType of
  isc_info_sql_records:
    for j := 0 to Count -1 do
    with Items[j] do
    case getItemType of
    isc_info_req_select_count:
      SelectCount := GetAsInteger;
    isc_info_req_insert_count:
      InsertCount := GetAsInteger;
    isc_info_req_update_count:
      UpdateCount := GetAsInteger;
    isc_info_req_delete_count:
      DeleteCount := GetAsInteger;
    end;
  end;
end;

function TFBStatement.GetSQLStatementType: TIBSQLStatementTypes;
begin
  Result := FSQLStatementType;
end;

function TFBStatement.GetSQLText: AnsiString;
begin
  Result := FSQL;
end;

function TFBStatement.GetProcessedSQLText: AnsiString;
begin
  if FProcessedSQL = '' then
    ProcessSQL(FSQL,FGenerateParamNames,FProcessedSQL);
  Result := FProcessedSQL
end;

function TFBStatement.GetSQLDialect: integer;
begin
  Result := FSQLDialect;
end;

procedure TFBStatement.Prepare(aTransaction: ITransaction);
begin
  if FPrepared then FreeHandle;
  if aTransaction <> nil then
  begin
    RemoveMonitor(FTransactionIntf as TFBTransaction);
    FTransactionIntf := aTransaction;
    AddMonitor(FTransactionIntf as TFBTransaction);
  end;
  InternalPrepare;
end;

function TFBStatement.Execute(aTransaction: ITransaction): IResults;
begin
  if aTransaction = nil then
    Result :=  InternalExecute(FTransactionIntf)
  else
    Result := InternalExecute(aTransaction);
end;

function TFBStatement.OpenCursor(aTransaction: ITransaction): IResultSet;
begin
  Close;
  if aTransaction = nil then
    Result := InternalOpenCursor(FTransactionIntf)
  else
    Result := InternalOpenCursor(aTransaction);
end;

function TFBStatement.CreateBlob(paramName: AnsiString): IBlob;
var column: TColumnMetaData;
begin
  InternalPrepare;
  column := SQLParams.ByName(paramName) as TSQLParam;
  if column = nil then
    IBError(ibxeFieldNotFound,[paramName]);
  Result := CreateBlob(column);
end;

function TFBStatement.CreateBlob(index: integer): IBlob;
begin
  InternalPrepare;
  Result := CreateBlob(SQLParams[index] as TSQLParam);
end;

function TFBStatement.CreateArray(paramName: AnsiString): IArray;
var column: TColumnMetaData;
begin
  InternalPrepare;
  column := SQLParams.ByName(paramName) as TSQLParam;
  if column = nil then
    IBError(ibxeFieldNotFound,[paramName]);
  Result := CreateArray(column);
end;

function TFBStatement.CreateArray(index: integer): IArray;
begin
  InternalPrepare;
  Result := CreateArray(SQLParams[index] as TSQLParam);
end;

function TFBStatement.GetAttachment: IAttachment;
begin
  Result := FAttachmentIntf;
end;

function TFBStatement.GetTransaction: ITransaction;
begin
  Result := FTransactionIntf
end;

function TFBStatement.GetDSQLInfo(Request: byte): ISQLInfoResults;
begin
  Result := TSQLInfoResultsBuffer.Create(FFirebirdClientAPI);
  GetDsqlInfo(Request,Result);
end;

procedure TFBStatement.SetRetainInterfaces(aValue: boolean);
begin
  RetainInterfaces := aValue;
end;

procedure TFBStatement.EnableStatistics(aValue: boolean);
begin
  if FCollectStatistics <> aValue then
  begin
    FCollectStatistics := aValue;
    FStatisticsAvailable := false;
  end;
end;

function TFBStatement.GetPerfStatistics(var stats: TPerfCounters): boolean;
begin
  Result := FStatisticsAvailable;
  if Result then
  begin
    stats[psCurrentMemory] := FAfterStats[psCurrentMemory];
    stats[psDeltaMemory] := FAfterStats[psCurrentMemory] - FBeforeStats[psCurrentMemory];
    stats[psMaxMemory] := FAfterStats[psMaxMemory];
    stats[psRealTime] :=  FAfterStats[psRealTime] - FBeforeStats[psRealTime];
    stats[psUserTime] :=  FAfterStats[psUserTime] - FBeforeStats[psUserTime];
    stats[psReads] := FAfterStats[psReads] - FBeforeStats[psReads];
    stats[psWrites] := FAfterStats[psWrites] - FBeforeStats[psWrites];
    stats[psFetches] := FAfterStats[psFetches] - FBeforeStats[psFetches];
    stats[psBuffers] :=  FAfterStats[psBuffers];
  end;
end;

end.

Revision:	263
Committed:	Thu Dec 6 15:55:01 2018 UTC (6 years ago) by tony
Content type:	text/x-pascal
Original Path:	*ibx/trunk/fbintf/client/FBStatement.pas*
File size:	11116 byte(s)
Log Message:	Release 2.3.2 committed
#	Content
1	(*
2	* Firebird Interface (fbintf). The fbintf components provide a set of
3	* Pascal language bindings for the Firebird API. Although predominantly
4	* a new development they include source code taken from IBX and may be
5	* considered a derived product. This software thus also includes the copyright
6	* notice and license conditions from IBX.
7	*
8	* Except for those parts dervied from IBX, contents of this file are subject
9	* to the Initial Developer's Public License Version 1.0 (the "License"); you
10	* may not use this file except in compliance with the License. You may obtain a
11	* copy of the License here:
12	*
13	* http://www.firebirdsql.org/index.php?op=doc&id=idpl
14	*
15	* Software distributed under the License is distributed on an "AS
16	* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
17	* implied. See the License for the specific language governing rights
18	* and limitations under the License.
19	*
20	* The Initial Developer of the Original Code is Tony Whyman.
21	*
22	* The Original Code is (C) 2016 Tony Whyman, MWA Software
23	* (http://www.mwasoftware.co.uk).
24	*
25	* All Rights Reserved.
26	*
27	* Contributor(s): ______________________________________.
28	*
29	*)
30	unit FBStatement;
31	{$IFDEF MSWINDOWS}
32	{$DEFINE WINDOWS}
33	{$ENDIF}
34
35	{$IFDEF FPC}
36	{$mode delphi}
37	{$codepage UTF8}
38	{$interfaces COM}
39	{$ENDIF}
40
41	interface
42
43	uses
44	Classes, SysUtils, IB, FBClientAPI, FBSQLData, FBOutputBlock, FBActivityMonitor,
45	FBTransaction;
46
47	type
48	TPerfStatistics = array[psCurrentMemory..psFetches] of Int64;
49
50	{ TFBStatement }
51
52	TFBStatement = class(TActivityReporter)
53	private
54	FAttachmentIntf: IAttachment;
55	FFirebirdClientAPI: TFBClientAPI;
56	protected
57	FTransactionIntf: ITransaction;
58	FExecTransactionIntf: ITransaction;
59	FSQLStatementType: TIBSQLStatementTypes; { Select, update, delete, insert, create, alter, etc...}
60	FSQLDialect: integer;
61	FOpen: boolean;
62	FPrepared: boolean;
63	FPrepareSeqNo: integer; {used to check for out of date references from interfaces}
64	FSQL: AnsiString;
65	FProcessedSQL: AnsiString;
66	FHasParamNames: boolean;
67	FBOF: boolean;
68	FEOF: boolean;
69	FSingleResults: boolean;
70	FGenerateParamNames: boolean;
71	FChangeSeqNo: integer;
72	FCollectStatistics: boolean;
73	FStatisticsAvailable: boolean;
74	FBeforeStats: TPerfStatistics;
75	FAfterStats: TPerfStatistics;
76	procedure CheckHandle; virtual; abstract;
77	procedure CheckTransaction(aTransaction: ITransaction);
78	procedure GetDsqlInfo(info_request: byte; buffer: ISQLInfoResults); overload; virtual; abstract;
79	procedure InternalPrepare; virtual; abstract;
80	function InternalExecute(aTransaction: ITransaction): IResults; virtual; abstract;
81	function InternalOpenCursor(aTransaction: ITransaction): IResultSet; virtual; abstract;
82	procedure ProcessSQL(sql: AnsiString; GenerateParamNames: boolean; var processedSQL: AnsiString); virtual; abstract;
83	procedure FreeHandle; virtual; abstract;
84	procedure InternalClose(Force: boolean); virtual; abstract;
85	function TimeStampToMSecs(const TimeStamp: TTimeStamp): Int64;
86	public
87	constructor Create(Attachment: IAttachment; Transaction: ITransaction;
88	sql: AnsiString; SQLDialect: integer);
89	constructor CreateWithParameterNames(Attachment: IAttachment; Transaction: ITransaction;
90	sql: AnsiString; SQLDialect: integer; GenerateParamNames: boolean =false);
91	destructor Destroy; override;
92	procedure Close;
93	procedure TransactionEnding(aTransaction: ITransaction; Force: boolean);
94	property SQLDialect: integer read FSQLDialect;
95	property FirebirdClientAPI: TFBClientAPI read FFirebirdClientAPI;
96
97	public
98	function GetSQLParams: ISQLParams; virtual; abstract;
99	function GetMetaData: IMetaData; virtual; abstract;
100	function GetRowsAffected(var SelectCount, InsertCount, UpdateCount,
101	DeleteCount: integer): boolean;
102	function GetSQLStatementType: TIBSQLStatementTypes;
103	function GetSQLText: AnsiString;
104	function GetProcessedSQLText: AnsiString;
105	function GetSQLDialect: integer;
106
107	{GetDSQLInfo only supports isc_info_sql_stmt_type, isc_info_sql_get_plan, isc_info_sql_records}
108	procedure Prepare(aTransaction: ITransaction=nil); virtual;
109	function Execute(aTransaction: ITransaction=nil): IResults;
110	function OpenCursor(aTransaction: ITransaction=nil): IResultSet;
111	function CreateBlob(paramName: AnsiString): IBlob; overload;
112	function CreateBlob(index: integer): IBlob; overload;
113	function CreateBlob(column: TColumnMetaData): IBlob; overload; virtual; abstract;
114	function CreateArray(paramName: AnsiString): IArray; overload;
115	function CreateArray(index: integer): IArray; overload;
116	function CreateArray(column: TColumnMetaData): IArray; overload; virtual; abstract;
117	function GetAttachment: IAttachment;
118	function GetTransaction: ITransaction;
119	function GetDSQLInfo(Request: byte): ISQLInfoResults; overload;
120	procedure SetRetainInterfaces(aValue: boolean); virtual;
121	procedure EnableStatistics(aValue: boolean);
122	function GetPerfStatistics(var stats: TPerfCounters): boolean;
123	property ChangeSeqNo: integer read FChangeSeqNo;
124	property SQLParams: ISQLParams read GetSQLParams;
125	property SQLStatementType: TIBSQLStatementTypes read GetSQLStatementType;
126	end;
127
128	implementation
129
130	uses FBMessages;
131
132	{ TFBStatement }
133
134	procedure TFBStatement.CheckTransaction(aTransaction: ITransaction);
135	begin
136	if (aTransaction = nil) then
137	IBError(ibxeTransactionNotAssigned,[]);
138
139	if not aTransaction.InTransaction then
140	IBError(ibxeNotInTransaction,[]);
141	end;
142
143	function TFBStatement.TimeStampToMSecs(const TimeStamp: TTimeStamp): Int64;
144	begin
145	Result := TimeStamp.Time + Int64(timestamp.date)*msecsperday;
146	end;
147
148	constructor TFBStatement.Create(Attachment: IAttachment;
149	Transaction: ITransaction; sql: AnsiString; SQLDialect: integer);
150	begin
151	inherited Create(Transaction as TFBTransaction,2);
152	FAttachmentIntf := Attachment;
153	FTransactionIntf := Transaction;
154	FFirebirdClientAPI := Attachment.getFirebirdAPI as TFBClientAPI;
155	FSQLDialect := SQLDialect;
156	FSQL := sql;
157	end;
158
159	constructor TFBStatement.CreateWithParameterNames(Attachment: IAttachment;
160	Transaction: ITransaction; sql: AnsiString; SQLDialect: integer;
161	GenerateParamNames: boolean);
162	begin
163	FHasParamNames := true;
164	FGenerateParamNames := GenerateParamNames;
165	Create(Attachment,Transaction,sql,SQLDialect);
166	end;
167
168	destructor TFBStatement.Destroy;
169	begin
170	Close;
171	FreeHandle;
172	inherited Destroy;
173	end;
174
175	procedure TFBStatement.Close;
176	begin
177	InternalClose(false);
178	end;
179
180	procedure TFBStatement.TransactionEnding(aTransaction: ITransaction;
181	Force: boolean);
182	begin
183	if FOpen and (FExecTransactionIntf = aTransaction) then
184	InternalClose(Force);
185
186	if FTransactionIntf = aTransaction then
187	begin
188	FreeHandle;
189	FPrepared := false;
190	end;
191	end;
192
193	function TFBStatement.GetRowsAffected(var SelectCount, InsertCount,
194	UpdateCount, DeleteCount: integer): boolean;
195	var
196	RB: ISQLInfoResults;
197	i, j: integer;
198	begin
199	InsertCount := 0;
200	UpdateCount := 0;
201	DeleteCount := 0;
202	Result := FPrepared;
203	if not Result then Exit;
204
205	RB := GetDsqlInfo(isc_info_sql_records);
206
207	for i := 0 to RB.Count - 1 do
208	with RB[i] do
209	case getItemType of
210	isc_info_sql_records:
211	for j := 0 to Count -1 do
212	with Items[j] do
213	case getItemType of
214	isc_info_req_select_count:
215	SelectCount := GetAsInteger;
216	isc_info_req_insert_count:
217	InsertCount := GetAsInteger;
218	isc_info_req_update_count:
219	UpdateCount := GetAsInteger;
220	isc_info_req_delete_count:
221	DeleteCount := GetAsInteger;
222	end;
223	end;
224	end;
225
226	function TFBStatement.GetSQLStatementType: TIBSQLStatementTypes;
227	begin
228	Result := FSQLStatementType;
229	end;
230
231	function TFBStatement.GetSQLText: AnsiString;
232	begin
233	Result := FSQL;
234	end;
235
236	function TFBStatement.GetProcessedSQLText: AnsiString;
237	begin
238	if FProcessedSQL = '' then
239	ProcessSQL(FSQL,FGenerateParamNames,FProcessedSQL);
240	Result := FProcessedSQL
241	end;
242
243	function TFBStatement.GetSQLDialect: integer;
244	begin
245	Result := FSQLDialect;
246	end;
247
248	procedure TFBStatement.Prepare(aTransaction: ITransaction);
249	begin
250	if FPrepared then FreeHandle;
251	if aTransaction <> nil then
252	begin
253	RemoveMonitor(FTransactionIntf as TFBTransaction);
254	FTransactionIntf := aTransaction;
255	AddMonitor(FTransactionIntf as TFBTransaction);
256	end;
257	InternalPrepare;
258	end;
259
260	function TFBStatement.Execute(aTransaction: ITransaction): IResults;
261	begin
262	if aTransaction = nil then
263	Result := InternalExecute(FTransactionIntf)
264	else
265	Result := InternalExecute(aTransaction);
266	end;
267
268	function TFBStatement.OpenCursor(aTransaction: ITransaction): IResultSet;
269	begin
270	Close;
271	if aTransaction = nil then
272	Result := InternalOpenCursor(FTransactionIntf)
273	else
274	Result := InternalOpenCursor(aTransaction);
275	end;
276
277	function TFBStatement.CreateBlob(paramName: AnsiString): IBlob;
278	var column: TColumnMetaData;
279	begin
280	InternalPrepare;
281	column := SQLParams.ByName(paramName) as TSQLParam;
282	if column = nil then
283	IBError(ibxeFieldNotFound,[paramName]);
284	Result := CreateBlob(column);
285	end;
286
287	function TFBStatement.CreateBlob(index: integer): IBlob;
288	begin
289	InternalPrepare;
290	Result := CreateBlob(SQLParams[index] as TSQLParam);
291	end;
292
293	function TFBStatement.CreateArray(paramName: AnsiString): IArray;
294	var column: TColumnMetaData;
295	begin
296	InternalPrepare;
297	column := SQLParams.ByName(paramName) as TSQLParam;
298	if column = nil then
299	IBError(ibxeFieldNotFound,[paramName]);
300	Result := CreateArray(column);
301	end;
302
303	function TFBStatement.CreateArray(index: integer): IArray;
304	begin
305	InternalPrepare;
306	Result := CreateArray(SQLParams[index] as TSQLParam);
307	end;
308
309	function TFBStatement.GetAttachment: IAttachment;
310	begin
311	Result := FAttachmentIntf;
312	end;
313
314	function TFBStatement.GetTransaction: ITransaction;
315	begin
316	Result := FTransactionIntf
317	end;
318
319	function TFBStatement.GetDSQLInfo(Request: byte): ISQLInfoResults;
320	begin
321	Result := TSQLInfoResultsBuffer.Create(FFirebirdClientAPI);
322	GetDsqlInfo(Request,Result);
323	end;
324
325	procedure TFBStatement.SetRetainInterfaces(aValue: boolean);
326	begin
327	RetainInterfaces := aValue;
328	end;
329
330	procedure TFBStatement.EnableStatistics(aValue: boolean);
331	begin
332	if FCollectStatistics <> aValue then
333	begin
334	FCollectStatistics := aValue;
335	FStatisticsAvailable := false;
336	end;
337	end;
338
339	function TFBStatement.GetPerfStatistics(var stats: TPerfCounters): boolean;
340	begin
341	Result := FStatisticsAvailable;
342	if Result then
343	begin
344	stats[psCurrentMemory] := FAfterStats[psCurrentMemory];
345	stats[psDeltaMemory] := FAfterStats[psCurrentMemory] - FBeforeStats[psCurrentMemory];
346	stats[psMaxMemory] := FAfterStats[psMaxMemory];
347	stats[psRealTime] := FAfterStats[psRealTime] - FBeforeStats[psRealTime];
348	stats[psUserTime] := FAfterStats[psUserTime] - FBeforeStats[psUserTime];
349	stats[psReads] := FAfterStats[psReads] - FBeforeStats[psReads];
350	stats[psWrites] := FAfterStats[psWrites] - FBeforeStats[psWrites];
351	stats[psFetches] := FAfterStats[psFetches] - FBeforeStats[psFetches];
352	stats[psBuffers] := FAfterStats[psBuffers];
353	end;
354	end;
355
356	end.
357