类型:转载 责任编辑:asp.net 日期:2007/05/23
热门软件下载:
有如下语句:
form1.Query1.Close;
form1.Query1.sql.Clear;
sqlnamestr:=delete from dataname
form1.Query1.SQL.Add(sqlnamestr;
form1.Query1.ExecSQL;
不能删除记录,但是只做了删除标记,而没有删除。
虽然用sql语句看不见,但是文件没有变小,用vfp打开,只做了删除标记。我用的是vfp的数据库。
网友回答:
// Pack a Paradox or dBASE table
// The table must be opened exclusively before calling this function...
procedure PackTable(Table: TTable);
var
Props: CURProps;
hDb: hDBIDb;
TableDesc: CRTblDesc;
begin
// Make sure the table is open exclusively so we can get the db handle...
if not Table.Active then
raise EDatabaseError.Create(Table must be opened to pack);
if not Table.Exclusive then
raise EDatabaseError.Create(Table must be opened exclusively to pack);
// Get the table properties to determine table type...
Check(DbiGetCursorProps(Table.Handle, Props));
// If the table is a Paradox table, you must call DbiDoRestructure...
if Props.szTableType = szPARADOX then begin
// Blank out the structure...
FillChar(TableDesc, sizeof(TableDesc), 0);
// Get the database handle from the tables cursor handle...
Check(DbiGetObjFromObj(hDBIObj(Table.Handle), objDATABASE, hDBIObj(hDb)));
// Put the table name in the table descriptor...
StrPCopy(TableDesc.szTblName, Table.TableName);
// Put the table type in the table descriptor...
StrPCopy(TableDesc.szTblType, Props.szTableType);
// Set the Pack option in the table descriptor to TRUE...
TableDesc.bPack := True;
// Close the table so the restructure can complete...
Table.Close;
// Call DbiDoRestructure...
Check(DbiDoRestructure(hDb, 1, @TableDesc, nil, nil, nil, False));
end
else
// If the table is a dBASE table, simply call DbiPackTable...
if (Props.szTableType = szDBASE) then
Check(DbiPackTable(Table.DBHandle, Table.Handle, nil, szDBASE, True))
else
// Pack only works on PAradox or dBASE; nothing else...
raise EDatabaseError.Create(Table must be either of Paradox or dBASE +
type to pack);
Table.Open;
end;
我记得这种数据库还有清除一下才可以彻底删除,可是很久不用了记不得用什么命令了。和FoxBase类似。关注一下。
用事务看看