Database Issues
The following issues should be taken into consideration when planning and configuring the campaign database:
Data representation
Softdial Campaign Manager™ can only deal with data types where the data can be represented as a string or number. This might cause problems if the customer data contained blob types.
On installation, Softdial Campaign Manager™ is configured to support ISO SQL2008 datatypes. If you are using a database that does not support these datatypes you can define alternative datatype support by setting the DBType registry key. See Registry Settings.
Order of processing
Database updates will be processed in the order in which they are listed within the update string. There is no way to guarantee the time frame in which the update will be performed, but updates will always take place in the order they are submitted.
Performance
Softdial Campaign Manager™ benefits from having a single service connecting to the RDBMS to marshall database access on behalf of lots of clients. Nevertheless, care should be taken to ensure that no single query will take a significant amount of time to execute.
Softdial Campaign Manager™ marshalls all database communication for a given campaign through a single thread. If a database update takes some seconds to execute, it may cause cache depletion as the request to move the cursor on the next N rows is behind the update in the thread's message queue.
Softdial Campaign Manager™ has some resilience built in against this scenario but, in extreme cases, long database update times would lead to call starvation (Softdial CallGem™ would run out of numbers to dial).
From V10.6.161 - now includes a mechanism to limit row count on column analysis cursor and main cursor to improve performance when using a large number of records (e.g. more than 200,000). The mechanism is controlled at a tenant level in the registry - HKEY_LOCAL_MACHINE\Software\Sytel\CMServer\[Tenant] (64bit OS) . See Registry Settings.
Stability issues
Most ODBC driver implementations rely on a permanently open TCP socket connection between the client (in this case Softdial Campaign Manager™ Server) and the DBMS. In the event of WAN outage, database overload scenarios and LAN overload/ outage scenarios, this results in a permanent database handle failure, resulting in the need to perform a full reconnect to the database.
The effect of such a disconnect is failure to perform database updates, leading to data integrity issues.
From V10.5 - an enhancement has been introduced to provide a transaction rollforward mechanism that enables Softdial Campaign Manager™ to manage temporary outages of up to 1 minute in duration.
Softdial Campaign Manager™ will close a running campaign as a result of a SQL statement failure on account of end-user syntax errors. Softdial Campaign Manager™ performs data validation in order to ensure that any SQL statement issued by Softdial Campaign Manager™ is correct; however SQL passed through to Softdial Campaign Manager™ from a customer script could cause a campaign to close.
A deadlock caused by a long-running customer query, or a sustained WAN outage, may also cause the campaign to close.
Softdial Campaign Manager™ allows transactions to be cached for up to one minute by default, before closing the campaign and writing the transaction cache to local storage for retry later.
It is not possible using a generic API (such as ODBC) to determine whether a statement failure is on account of a user syntax error or is on account of communication error, deadlock or some other environmental failure.
In order to have a scheme for rollforward on environmental failure this mechanism is also invoked if a syntax error occurs.
This is an unavoidable consequence of implementing a HA (high availability) scheme and requires customers to be diligent in testing any script configurations that call SQL statements through the Data Query and Data Lookup APIs.
Testing of 'Failed' state
Softdial Campaign Manager™ Server implements a test mode API which can be used to force the database connection into a failed state in order to facilitate testing of the recovery and rollforward mechanism. The message detail is documented below.
This information is intended to provide experienced DB users with a means of making a manual test within a customer database environment.
- In the event of a database statement execution failure, Softdial Campaign Manager™ operates in database failed mode and attempts to catch up every 5 seconds.
- If within one minute Softdial Campaign Manager™ has not been able to catch up, the failure is deemed to be permanent and the campaign is stopped. Unprocessed database transactions are written to disk, and then read in and rolled forward on campaign restart.
- This mechanism may be tested by sending the following Force Failed [FF] message.
- To force Softdial Campaign Manager™ temporarily into database failed mode (that Softdial Campaign Manager™ will recover from), send the following message in Dialer Chat:
CM:DE:FF\TD<tenant>\CY<Campaign ID>\OIfoo
- To force a permanent failure, issue the same message with the On/ Off (ON) parameter.
- To force Softdial Campaign Manager™ temporarily into database failed mode (that Softdial Campaign Manager™ will recover from), send the following message in Dialer Chat:
- You will see that Softdial Campaign Manager™ raises various Notify Event [NE] messages during its failover and recovery.
Updating the database while the campaign is running
To enable updates to be performed reliably without risk of deadlocks and data corruption, the Campaign Table must only be updated using the API provided. See Updating Campaign Tables for details.
Database columns types
Softdial Campaign Manager™ database columns are typed as follows:
| Description | Mandatory? | Type created by CM | Generic type |
|---|---|---|---|
| Switch Result | Yes | SMALLINT | Signed integer 16 bits or more |
| Agent Result | Yes | SMALLINT | Signed integer 16 bits or more |
| Result Timestamp | No | FLOAT | Decimal number with 6.6 precision |
| Retry Count | Yes | SMALLINT | Signed integer 16 bits or more |
| Retry Timestamp | Yes | FLOAT | Decimal number with 6.6 precision |
| Retry Username | Yes | VARCHAR(80) | Fixed or variable character string with not less than 80 chars |
| Callback number | Yes | VARCHAR(80) | Fixed or variable character string with not less than 80 chars |
| Retry Index | Yes | SMALLINT | Signed integer 16 bits or more |
| Timezone lower bound | No | FLOAT | Decimal number with 1.3 precision |
| Timezone upper bound | No | FLOAT | Decimal number with 1.3 precision |
| Postcode Column | No | VARCHAR(80) | Fixed or variable character string no size constraint |
| Legislature (state) code | No | VARCHAR(80) | Fixed or variable character string no size constraint |
| Multiple number priority | No | SMALLINT | Signed integer 16 bits or more |