parquet_get_col_size Interface

interface
public module subroutine parquet_get_col_size(reader, name, col_size)

Arguments

Type IntentOptional Attributes Name
type(parquet_reader), intent(in) :: reader

open reader.

character(len=*), intent(in) :: name

column name.

integer, intent(out) :: col_size

that column's declared element count.

Description

Returns name's declared col_size (vector-column element count; 1 for a scalar column) in col_size. Reads no column data for a scalar column or a FIXED_SIZE_LIST one (whose width is a schema-level constant), so this is safe even on a column whose total element count (nrows * col_size) itself exceeds int32. A plain LIST/LARGE_LIST column -- which this library never writes, but another producer may -- has no schema-level width at all, so it is screened from the footer and then proven one row group at a time: that does read data, but never holds more than one row group. See parquet_get_column_total_elements, which answers via the same helper.