dBase/Paradox檔案的最大極限

BDE在16和32位元版本上Borland資料庫引擎與對相應dBase/Paradox檔案的最大極限到哪里。在此我們列出一些有用且常見的BDE物件最大限制(分成General, dBASE , Paradox三份清單)。 如果無法達到這些需求或是有記憶體不足的訊息,請試著將BDE中的SHAREDMEMSIZE設定調成4096或一直加大到符合你的需求。

General Limits
48 Clients in system
32 Sessions per client (3.5 and earlier, 16 Bit, 32 Bit)
256 Session per client (4.0, 32 Bit)
32 Open databases per session (3.5 and earlier, 16 Bit, 32 Bit)
2048 Open databases per session (4.0, 32 Bit)32 Loaded drivers
64 Sessions in system (3.5 and earlier, 16 Bit, 32 Bit)
12288 Sessions in system (4.0, 32 Bit)
4000 Cursors per session
16 Entries in error stack
8 Table types per driver
16 Field types per driver
8 Index types per driver
48K Size of configuration (IDAPI.CFG) file
64K Size of SQL statement (RequestLive=False)
4K Size of SQL statement (RequestLive=True)
6K Size of SQL statement (RequestLive=True) (4.01, 32 Bit)
16K Record buffer size (SQL or ODBC)
31 Table and field name size in characters
64 Stored procedure name size in characters
16 Fields in a key
3 File extension size in characters
260 Table name length in characters(some servers might have other limits)
260 Path and file name length in characters


dBASE Limits
256 Open dBASE tables per system (16 Bit)
350 Open dBASE tables per system (BDE 3.0 - 4.0, 32 Bit)
512 Open dBASE tables per system (BDE 4.01, 32 Bit)
100 Record locks on one dBASE table (16 and 32 Bit)
100 Records in transactions on a dBASE table (32 Bit)
1 Billion records in a table
2 Billion bytes in .DBF (Table) file
4000 Size in bytes per record (dBASE 4)
32767 Size in bytes per record (dBASE for Windows)
255 Number of fields per table (dBASE 4)
1024 Number of fields per table (dBASE for Windows)
47 Number of index tags per .MDX file
254 Size of character fields
10 Open master indexes (.MDX) per table
220 Key expression length in characters


Paradox Limits
127 Tables open per system (4.0 and earlier, 16 Bit, 32 Bit)
254 Tables open per system (4.01, 32 Bit)
64 Record locks on one table (16Bit) per session
255 Record locks on one table (32Bit) per session
255 Records in transactions on a table (32 Bit)
512 Open physical files (4.0 and earlier, 16 Bit, 32 Bit)(DB, PX, MB, X??, Y??, VAL, TV)
1024 Open physical files (4.01, 32 Bit)(DB, PX, MB, X??, Y??, VAL, TV)
300 Users in one PDOXUSRS.NET file
255 Number of fields per table
255 Size of character fields
2 Billion records in a table
2 Billion bytes in .DB (Table) file10800 Bytes per record for indexed tables32750 Bytes per record for non-indexed tables
127 Number of secondary indexes per table
16 Number of fields in an index
255 Concurrent users per table
256 Megabytes of data per BLOb field
100 Passwords per session
15 Password length
63 Passwords per table
159 Fields with validity checks (32 Bit)
63 Fields with validity checks (16 Bit)

該文檔中對您所提出的疑惑有很好的幫助.

Paradox資料庫中的Table的最大容量一般爲128M,但是可以擴展的:
1.打開BDE Administrator
2.選Configuration頁
3.選driver
4.選native
5.選paradox
6.右邊:選block size, 一般的是2048, 最小的,改個高的。如果改到32768, 可以支援到2G, 應該夠用了吧。

PS:)再囉嗦一句:Paradox和dBase中的Table Name被限制爲八個字元。dBase中的列名稱被限制爲10個字元。

posted on 2005-10-18 17:17  Kouwell  阅读(492)  评论(0编辑  收藏  举报

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