|
在delphi4.0中如何真正删除dbf文件记录，DBIPACKTABLE具体如何用(100分)
问题的分类是：数据库 - 文件型 , 分坛主: SeaSky, 分坛主: yifeng 来自：sxzww 时间：00-3-11 11:11:10 ID:197921 我的语句如下： sql.clear; SQL.ADD('delete from xz_jybj'); q2.execsql; close; 执行后，只在数据文件xz_jybj中做了删除标记， 我查询过这个站点关于delete 记录的有关内容，似乎可以用DBIPACKTABLE 函数,但我看不懂,谁能帮助我，谢谢 。 -------------------------------------------------------------------------------- 来自：xWolf 时间：00-3-11 11:37:56 ID:197934 procedure PackTable(Table: TTable); var Props: CURProps; begin // 必须以独占方式打开 if (not Table.Active) or (not Table.Exclusive) then Exit; Check(DBIGetCursorProps(Table.Handle, Props)); // 必须是dBase或FoxPro if Props.szTableType <> szDBASE then Exit; Check(DBIPackTable(Table.DBHandle, Table.Handle, nil, szDBASE, True)); Table.Open; end; -------------------------------------------------------------------------------- 来自：xWolf 时间：00-3-11 11:47:51 ID:197941 function DbiPackTable (hDb: hDBIDb; hCursor: hDBICur; pszTableName: PChar; pszDriverType: PChar; bRegenIdxs: Bool): DBIResult stdcall; 参数说明: hDB: 数据库句柄,可以由TTable.DBHandle得到 hCursor: 数据表关联的游标,若为nil则数据表依赖于pszTableName和pszDriverType bRegenIdxs决定是否关联外接的索引文件尤其是MDX多索引文件 以下摘自Delphi Help Example 1: Pack a Paradox or dBASE table. This example will pack a Paradox or dBASE table therfore removing already deleted rows in a table. This function will also regenerate all out-of-date indexes (maintained indexes). This example uses the following input: PackTable(Table1) The function is defined as follows: // Pack a Paradox or dBASE table // The table must be opened execlusively 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 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; -------------------------------------------------------------------------------- 来自：sxzww 时间：00-3-11 15:36:04 ID:198012 接受答案了. |