HP 3000 Manuals HP 3000 Manuals
Appendix A ALLBASE/SQL Limits
The tables below present logical and physical system limits for
ALLBASE/SQL. The values show the maximums permitted by the ALLBASE/SQL
software. In practice, lower maximums may be imposed by the operating
system or hardware environment in which ALLBASE/SQL is installed. In
addition, ALLBASE/SQL uses some space per page for internal data
structures. This leaves less than a complete page available to the user
for tuple data and header storage. Refer to the "Logical Design" and
"Physical Design" chapters for methods of determining the amount of space
available to the user.
Page size is 4096 bytes, except for log pages, which are 512 bytes.
Table A-1. System Control Limits
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- Name of Limit - Value -
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- Multiuser DBEnvironments per system - No limit -
- Single-user DBEnvironments per system - No limit -
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| [REV BEG] | |
| Number of concurrent sessions | Limited by Runtime Control Block Allocation |
| Number of concurrent transactions | 2 to 240 (when 240 are active, additional |
| | transactions are placed in a wait |
| | queue)[REV END] |
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- Number of concurrent connections per user - 1 to 32[REV BEG] -
- Number of concurrent users - No limit[REV END] -
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| Timeout value | 1 to 2,147,483,647 seconds or 1 to |
| | 35,791,394 minutes |
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Table A-2. Logical Data Limits
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- Name of Limit - Value -
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- Tables per DBE - 231 - 1 -
- Maximum columns per table - 1023 -
| Bytes per row | (NumberOfColumns+1)*2+SumOfColumnLengths <= 4000 (for |
| | the VARCHAR data type, ColumnLength equals |
| | ColumnValueLength) |
- Bytes per column - 3996 -
- Bytes per long column - 231 - 1 -
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- Views per DBE - 231 - 1 -
- Maximum columns per view - 1023 -
| Maximum parameters per | 1023 |
| procedure | |
| Maximum result columns per | 1024 |
| procedure | |
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Table A-2. Logical Data Limits (cont.)
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- Name of Limit - Value -
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- Indexes per DBEnvironment - 231 - 1 -
| Maximum columns per B-tree | 16 |
| index or hash | |
| Maximum columns per virtual | 15 |
| index (PCR) | |
| Maximum B-tree or hash key | (NumberofKeyColumns + 2)*2 + SumofColumnLengths +8 <= |
| size | 1024 |
| Maximum virtual index (PCR) | (NumberofKeyColumns + 3)*2 + SumofColumnLengths +10 <= |
| key size | 1024 |
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- Maximum sort columns - 1023 -
| Maximum sort tuple size | (NumberOfSortColumns + 1)*2 + SumOfSortColumnLengths |
| | <=4000 (for the VARCHAR data type, ColumnLength equals |
| | ColumnValueLength) |
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Table A-3. Space Management Limits
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- Name of Limit - Value -
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| Tables per statement (including tables underlying | 31 |
| views) | |
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- Query blocks per query - 16 -
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- Data and index page size - 4096 bytes -
- Log page size - 512 bytes -
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- Pages per DBEFile (except DBEFile0) - 2 to 219 - 1 -
- Pages per DBEFile0 (one per DBEnvironment) - 150 to 219 - 1 -
- DBEFiles per DBEnvironment - 32767 -
- Pages per DBEFileSet (when there is only one) - (32767)(219 - 1) -
- Pages per DBEnvironment (all DBEFiles combined) - (32767)(219 - 1) -
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- Log size (pages) - 250 to 222 - 1 -
- Maximum size of a single log file - 4 gigabytes -
- Maximum number of log files - 34 -
- Maximum size of log file space - 136 gigabytes -
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- Number of data buffer pages - 15 to 50000 -
- Number of log buffer pages - 24 to 1024[REV BEG] -
- Number of runtime control block pages - 17 to 2000 -
| Total of data buffer pages and runtime control | 256 Mbytes |
| block pages | |
- Number of shared memory objects - 72[REV END] -
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- ISQL command size - 32K bytes -
- Maximum levels of nesting for ISQL STARTs per user - 10 -
- SQL command size - 32K bytes -
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| Number of pages per file opened in a TempSpace | 128 to 524284 |
| (MaxFilePages) | |
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