Maximale Anzahl Felder in einer Tabelle ?

[Stefan Sonner]

Hi ihr,

weiss von Euch jemand, ob es von der BDE her eine Einschränkung gibt, wieviele Felder eine Tabelle maximal haben darf ?

danke mal !
stefan

[Andreas Kosch]

Hallo,

das hängt davon ab, welche Datenbank verwendet wird. Borland stellt in einer <b>Technical Information</b> (TI) die folgenden Daten zur Verfügung:
<pre>
General BDE Limitations 48 Clients in system
<br>
32 Sessions per client (3.5 and earlier, 16 Bit, 32 Bit)
256 Session 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
<br>
Paradox Limitations
<br>
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)
<br>
dBASE 5.x and earlier / FoxPro Limitations
</br>
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)
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
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