谢谢各位帮助，我想删除已存在删除标记的记录，请问怎么办？ fox中的方法是： use tem pack//删除已存在删除标记的记录,delphi中用什么语句呢？
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 table's 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;
用table1.EmptyTable; 这种方法可以删除几百K字节数的数据库 而当删除一个数据库是2.7M时，就出现了Table is busy这个提示，
用TTABLE控件，你可以做一下！应该能行的！
建议用TTabletable1.EmptyTable; delete from 的方法在删纪录几万条时会出错。
1: select * into #temptable from tablename where 1=2 2: drop table tablename 3: select * into tablename from #temptable
query1.close; query1.sql.clear; query1.sql.add('select * into tem from czb where 1=2'); query1.execsql; 上面的语句错在那儿呢，请教！！
fox中的方法是：
use tem
pack//删除已存在删除标记的记录,delphi中用什么语句呢？
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 table's 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;
而当删除一个数据库是2.7M时，就出现了Table is busy这个提示，
2: drop table tablename
3: select * into tablename from #temptable
query1.sql.clear;
query1.sql.add('select * into tem from czb where 1=2');
query1.execsql;
上面的语句错在那儿呢，请教！！
query1.close;
query1.sql.clear;
query1.sql.add('select * into tem from czb where 1=2');
query1.execsql;
上面的语句错在那儿呢，请教！！ select 时请用Query1.Open;