Creates a volcano-style raster plot of differential methylation results using database-backed plotting via `dbplot`. This function connects to a DuckDB database, retrieves the specified differential methylation table, filters and transforms the data, and generates a raster plot with `meth_diff` on the x-axis and `-log10(p-value)` on the y-axis.
Arguments
- mod_db
A `mod_db` object or a character string representing the file path to a DuckDB database. The database must contain a table with differential methylation results.
- table
A character string specifying the name of the table in the database containing the differential methylation data. The table must contain at least the following columns: `meth_diff` and `p_val`.
Value
Invisibly returns the `mod_db` object after closing the database connection. The function prints the ggplot2 raster plot to the active R graphics device.
Details
The plot uses `dbplot::dbplot_raster()` to efficiently create a raster visualization of large-scale methylation difference data. It applies a log10 transformation to the `p_val` column and uses a color gradient to show the density of observations in each bin. A message is printed to indicate the time taken to generate the plot.