Data Retrieval Support
In response to read and selectdb ProcScript instructions, Uniface issues connector requests to select data into a hitlist and fetch it into the calling component. Special considerations and restrictions may apply for some databases.
- Most databases support stepped hitlists to improve performance.
- For some databases, the use of selectdb functions may be restricted, depending on the DBMS data type of the field.
- The offset option of the read ProcScript statement is not supported by all connectors.
- Record-level databases do not support the where, order by, and u_where arguments to the read statement or the retrieveSequential trigger.
For more information, see read and selectdb. For details about the data retrieval support provided by specific connectors, see the following table.
Connector |
Stepped hitlist? |
|
|
|
|
|
retrieveSequential Trigger |
Details |
---|---|---|---|---|---|---|---|---|
DB2 |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For more information, see Data Retrieval on DB2. |
Informix |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
Yes |
For more information, see Data Retrieval on Informix. |
LDAP |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
Yes |
For more information, see Data Storage and Retrieval on LDAP and Map LDAP Entries to Uniface Entities. |
MS-SQL Server |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For more information, see Data Retrieval on Microsoft SQL Server . |
MySQL |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For more information, see Data Retrieval on MySQL. |
ODBC |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
Yes |
For more information, see Data Retrieval on ODBC. |
Oracle |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For more information, see Data Retrieval on Oracle. |
PostgreSQL |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
|
SEQ |
No |
No |
Yes |
Yes |
No |
Yes |
No |
For more information, see Data Retrieval on SEQ. |
SQLite |
Yes 1 |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For more information, see Data Retrieval on SQLite and Locking Considerations for SQLite. |
Sybase |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
No |
For more information, see Data Retrieval on Sybase . |
TXT |
No |
No |
No |
No |
No |
No |
|
|
|