DBF size restrictions/limits

[Vic Wolyncevic]

Does anyone know where the specs and size limitations
are documented for DBF tables. I am sure I have seen
them somewhere but I can't find them when I need them. I
am looking at things like maximum fields allowable in a
table, rowset volume limitations, maximum allowable for
numeric/character fields etc.

Thanks,

Vic

[Ken Mayer [dBASE, Inc.]]

Vic Wolyncevic <vwol...@powerup.com.au> wrote:

Have you looked in the Knowledgebase? I am pretty sure it's there.

Ken
---
Ken Mayer [dBASE, Inc.]
** Please respond ONLY in the newsgroups **

"Think OOP"

dBASE, Inc. website: http://www.dbase.com

[Jean-Pierre Martel]

In article <MPG.163b4e7ad...@news.dbase2000.com>,
vwol...@powerup.com.au says...

> Does anyone know where the specs and size limitations
> are documented for DBF tables. I am sure I have seen
> them somewhere

You will find some of these limitations in the section "The BDE limits",
inside the article called "The dBASE Tables" in the issue no. 12 of the
dBulletin.

Jean-Pierre Martel, editor
The dBASE Developers Bulletin

[Ivar B. Jessen]

On Sat, 20 Oct 2001 09:04:44 +1000 , in dbase.programming , DBF
size restrictions/limits , Vic Wolyncevic <vwol...@powerup.com.au>
wrote:

For table level 7 structure see knowledgeBase\int\db7_file_fmt.htm.

Romain once posted the list below concerning BDE objects, which might
be of some help.

Ivar B. Jessen

***********
BDE Objects, maximum limits

I found this by pure chance and post a copy here to have it in our
archives.
------------

Below are the maximum limits for some common BDE objects.
If you find you cannot reach these limits or are getting
an out of memoryerror, increasing your SHAREDMEMSIZE in
BDE Config to 4096 or more should allow you to reach these limits.
If available, also setthe MEMSIZE setting to 24 in all cases.

General BDE Limitations 48 Clients in system
32 Sessions per client (3.5 and earlier, 16 Bit, 32 Bit)
256 Sessions per client (4.0 & later, 32 Bit)
64 Sessions with a cursor open per client (4.0 & later, 32 Bit)
32 Open databases per session (3.5 and earlier, 16 Bit, 32 Bit)
2048 Open databases per session (4.0 & later, 32 Bit)
32 Loaded drivers
64 Sessions in system (3.5 and earlier, 16 Bit, 32 Bit)
12288 Sessions in system (4.0 & later, 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 Max size of SQL statement (RequestLive=False)
4K Max size of SQL statement (RequestLive=True)
6K Max size of SQL statement (RequestLive=True) (BDE 4.01 & later)
16K Record buffer size (SQL and ODBC)
31 Table and field name size in characters
64 Stored procedure name size in characters
16 Fields in 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
260 Index name length (including pseudo-indexes)
204 Setting for MEMSIZE in BDE Administrator
127 Tables with cached updates applied (4.0 & earlier, 32 Bit)
254 Tables with cached updates applied (4.01 & later, 32 Bit)
380 Maximum number of fields in Table for DbiCreateTable with
Interbase
254 Maximum number of fields in Table for DbiCreateTable with Oracle
500 Maximum number of fields in Table for DbiCreateTable with Informix

252 Maximum number of fields in Table for DbiCreateTable with MSSQL
250 Maximum number of fields in Table for DbiCreateTable with ODBC,
Sybase
253 Maximum number of fields in Table for DbiCreateTable with DB2
408 Maximum number of fields used in an Interbase Table
1000000 Maximum number of bytes per blob for ODBC

Paradox Limitations 127 Tables open per system
254 Tables open per system (BDE 4.01 & later)
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 (DB, PX, MB, X??, Y??, VAL, TV)
1024 Open physical files (DB, PX, MB, X??, Y??, VAL, TV) (BDE 4.01 &
later)
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) file
10800 Bytes per record for indexed tables
32750 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)
81 Maximum characters in path for tables involved in Referential
Integrity

dBASE 5.x and earlier / FoxPro Limitations 32 Sessions containing a
cursor to a table
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 & later, 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)
128 Number of fields per table (FoxPro, if a memo field is present)
256 Number of fields per table (FoxPro, if no memo fields in table)
2.6 Highest FoxPro table version supported
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

--------------------------------------------------------------------------------

DISCLAIMER: You have the right to use this technical information
subject
to the terms of the No-Nonsense License Statement that you received
with
the Borland product to which this information pertains.
--
Romain Strieff [dBVIPS]
************

[Dennis R. Levy]

Are you saying that with db2k that you are limited to 48 concurrent users in the
program at one time and that this is a BDE limit? In 5.7, we had as many as 300
concurrent users and the army had 150 concurrent users? What gives?

"General BDE Limitations 48 Clients in system"

Dennis Levy

[David Kerber]

To me that would mean 48 'clients' (i.e. programs) using the same copy
of the BDE, not network clients on the LAN. There are plenty of people
here with systems having more than that number of LAN clients using the
same databases.

--

Dave Kerber
Edit the return address by removing the ns_ before e-mailing

This message was entirely written using recycled electrons.

REAL programmers write self-modifying code, leading to:
Why there is ALWAYS one more bug (courtesy of O.D. Williams):
1. Debuging code is always much harder than writing it.
2. Therefore, if your code is as clever as you are capable of making
it, you are, by definition, inadequate to debug it.