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Note: The Professional Panels functionality includes no built-in limits. However, due to the time and resources used when processing large databases, you are strongly recommended to keep within the following maximum values:
- Number of panelists – is dependent on the type of license you have:
- On Premise - up to 10 million.
- On Demand - up to 5 million. Panels larger than this must be approved in advance by the Forsta On Demand Operations team - contact support@confirmit.com, or an On Premise installation should be considered.
- Survey history – up to 100 million records.
- Maximum number of variables in a panel - 500
- Maximum number of Columns in panel database - 4000
Each single, numeric, date and open text question will occupy one column in the panel database. Multi questions will occupy one column per answer alternative.
- Sampling (Memory on batch server, read from BitStream server and SQL server) – a maximum of 8 dimensions.
- Maximum number of cells in the sampling matrix – 100.000. This is calculated as the number of segments in each dimension multiplied by the number of segments in the other dimensions. For example, if the matrix has 8 dimensions, where the number of segments is n1 in dimension 1, n2 in dimension 2 etc. the total number of cells will be n1*n2*n3*n4*n5*n6*n7*n8. This value must be a maximum of 100.000.
- Be aware that large BitStream generations will use considerable server processing resources, and can cause delays for other users. Large BitStream generations should therefore be performed during off-peak hours.
- BitStream file set generation affects the BitStream server during generation and sampling, and will affect the SQL server (reading) to a lesser degree. Therefore:
- Limit the number of open text fields included when sampling. BitStream files should only include the fields to be used in filtering and sampling matrices, not the fields you need for the respondent file.
- Open text fields that are to be part of the BitStream files should be limited to 4 characters.
- Note that Open text fields are not supported as segments in the sampling matrix.
- To optimize the panel database: use Boolean data types and numeric codes whenever possible, and numeric ranges between 0 and 255 should be specified.
- The “Panelist registration / update profile project” checkbox in the Project Overview page should only be used for surveys used for panelists signing up for the panel and updating their profile. It must not be used regular data collection (research projects/surveys). If this box is checked for a project, it will be registered in the project log.
- “Sample Only” surveys (add-on) are intended only for access panel providers that sell sample to 3rd parties, for surveys for which the access panel provider does not run the data collection. The surveys used to redirect panelists to external survey links and update status upon survey completion can contain up to 5 additional questions (for example for rating the survey experience etc.), but are not to be used for regular additional data collection.
Note: The actual limits will depend on the hardware configuration currently in use. Contact Forsta Support for further information.