Crosstab Reports

Developer guide for the Enezaframework reporting engine. Part of the Add Report series.

Overview
How a Crosstab Is Built
Attributes
Example
Validation
Related Guides

Overview

CrosstabReportView produces a two-dimensional pivot table: one axis is group_by, the other is crosstab_field, and each cell holds a computation (for example, __total__).

How a Crosstab Is Built

flowchart LR
    ROWS["Source rows<br/>report_model queryset"] --> GROUP["Group by<br/>group_by"]
    ROWS --> PIVOT["Pivot by<br/>crosstab_field"]
    GROUP --> CELLS["Cell values<br/>crosstab_columns"]
    PIVOT --> CELLS
    CELLS --> REM{"Include remainder?"}
    REM -->|"Yes (default)"| OTHER["Add 'other' column"]
    REM -->|"No"| OUT["Pivot table"]
    OTHER --> OUT

Attributes

Attribute	Required	Description
`report_model`	Yes	Django model for the data source.
`group_by`	Recommended	Field used for the row axis.
`crosstab_field`	Yes	FK or char field to pivot on (for example `"product"`).
`crosstab_columns`	Yes	Computation fields per crosstab cell.
`crosstab_ids`	No	Restrict the pivot to specific IDs.
`crosstab_ids_custom_filters`	No	Custom filters applied to the pivot IDs.
`crosstab_compute_remainder`	No	Include an "other" column (default: `True`).
`crosstab_precomputed`	No	Read pre-aggregated values from the database.
`date_field`	No	Date field for date-range filtering.
`columns`	No	Extra leading columns (for example `["region__name"]`).

Example

python

from enezareporting.report_base import CrosstabReportView
from enezareporting.parameters import ParameterSet, DateRangeParam
from myapp.models import SalesLine


class RegionByProduct(CrosstabReportView):
    report_title = "Region by Product"
    report_model = SalesLine
    date_field = "date_placed"
    group_by = "region"
    crosstab_field = "product"
    crosstab_columns = ["__total__"]
    columns = ["region__name"]
    parameter_spec = ParameterSet(
        DateRangeParam(name="date_range", start_field="date_placed"),
    )

Validation

CrosstabReportView validates at class-creation time. Missing crosstab_field or crosstab_columns raises ImproperlyConfigured:

text

ImproperlyConfigured: <ClassName>: crosstab_field must be provided for CrosstabReport
ImproperlyConfigured: <ClassName>: crosstab_columns must be provided for CrosstabReport