Limitations exist on the size of objects and the number of objects in Sybase IQ databases. In most cases, computer memory and disk drive are more limiting factors.
For limitations that apply to only one platform, see the platform-specific documentation.
Item |
Limitation |
|---|---|
Catalog file size |
Maximum is 1TB for all platforms. Windows systems with NTFS support the 1TB maximum. |
Database name size |
250 bytes |
Database size |
Maximum database size approximates the number of files times the file size on a particular platform, depending on the maximum disk configuration. Refer to your operating system documentation for kernel parameters that affect the maximum number of files. |
Dbfile size |
Determined by the operating system file size |
Dbspace size |
Raw device: Maximum size is 4T. File system device: Maximum size is 4TB Operating system file: Maximum size supported by the operating system Sybase does not recommend creating dbspaces on NAS (Network Attached Storage) devices |
Field size |
255 bytes for BINARY, 32,767 bytes for VARBINARY 32,767 for CHAR, VARCHAR Up to 512 TB for 128 KB pages or 1 PB for 512 KB pages for LONG BINARY, LONG VARCHAR |
IQ page size |
Must be between 64KB and 512KB |
Maximum key size |
255 bytes for single-column index. 5300 bytes for multicolumn index |
Maximum length of string literal |
32KB |
Maximum length of SQL statement |
The maximum length of SQL statements is limited to the amount of memory available for the IQ catalog, and to the size of the catalog stack If your SQL statements are long, increase the catalog stack size using -gss, and increase catalog memory cache size using -c or a combination of -ch and -cl When printing the SQL statement in error messages, the text is limited to the IQ catalog page size. To print long commands, you can start the server with an increased -gp setting, although in general Sybase recommends that you use the default of -gp 4096. |
Maximum length of variable-length FILLER column |
512 bytes |
Maximum number of dbfiles |
The total number of files that can be opened depends on the number of unique file descriptors that an operating system can support |
Maximum number of users (connected and concurrent) |
1000 on 64-bit platforms AIX, HP, Linux, and Sun Solaris 200 on 64-bit platforms on Windows |
Maximum size of temp extract file |
Set by TEMP_EXTRACT_SIZEn option. Platform limits are: AIX & HP-UX: 0 – 64GB Sun Solaris: 0 – 512GB Windows: 0 – 128GB Linux: 0 – 512GB |
Number of columns per table |
Sybase IQ supports up to 45,000 columns in a table. You may see performance degradation if you have more than 10,000 columns in a table. The limit on the number of columns per table that allow NULLs is approximately 8*(database-page-size - 30). |
Number of events per database |
2^31 – 1 = 2 147 483 647 |
Number of files per database |
Operating system limit that user can adjust; for example, using NOFILE. Typically, 2047 files per database |
Number of indexes |
2^32 (~4,000,000) per table |
Number of rows per table |
Limited by table size, upper limit 2^48 -1 |
Number of stored procedures per database |
2^32 – 1 = 4 294 967 295 |
Number of tables or views in a single FROM clause |
16 – 64, depending on the query, with join optimizer turned on |
Number of tables or views referenced per query |
512 |
Number of tables per database |
4,293,918,719 |
Number of tables per join index (number of tables that can be joined in one query block) |
31 |
Number of tables referenced per transaction |
No limit. |
Number of UNION branches per query |
512. If each branch has multiple tables in the FROM clause, the limit on tables per query reduces the number of UNION branches allowed. |
Number of values in an IN list |
250,000 |
Row size |
Sybase recommends a limit of half the page size |
Table size |
Limited by database size |