delphi ADOQuery多线程查询

最新推荐文章于 2023-03-13 17:30:14 发布

转载最新推荐文章于 2023-03-13 17:30:14 发布 · 1.5k 阅读

本文介绍了一种使用多线程进行数据库查询的方法，通过创建一个继承自TThread的TSelect类来实现并发查询，提高了查询效率。需要注意的是，在执行查询过程中要初始化COM库并确保其正确释放。

多线程查询

//==============================================================================
// 多线程查询 cxg 2008-09-26 14:29:42
//==============================================================================

unit uSelect;

interface

uses
sysUtils,ADODB,Classes;

type
TSelect = class(TThread)
private
FAdoConnection:TADOConnection;
FAdoquery:TADOQuery;
FSql:String;
protected
procedure Execute;override;
public
constructor create(AdoConnection:TADOConnection;AdoQuery:TADOQuery;Sql:string);
end;

implementation

{ Tselect }

constructor Tselect.create(AdoConnection:TADOConnection;AdoQuery:TADOQuery;Sql:string);
begin
inherited create(False);
FreeOnTerminate:=True;
FAdoConnection:=AdoConnection;
FAdoquery:=AdoQuery;
FSql:=Sql;
end;

procedure Tselect.Execute;
begin
with FAdoquery do
begin
Close;
SQL.Clear;
SQL.Add(fsql);
Open;
end;
end;

end.

1楼 schinar 2012-04-11 20:20发表 [回复] 代码中需要加入use activex;
exeute 过程中需要修改成
CoInitialize(nil);
with FAdoquery do
begin
Close;
SQL.Clear;
SQL.Add(fsql);
Open;
end;
CoUninitialize;代码中需要加入use activex;
exeute 过程中需要修改成
CoInitialize(nil);
with FAdoquery do
begin
Close;
SQL.Clear;
SQL.Add(fsql);
Open;
end;
CoUninitialize;
.