parquet_column_info Derived Type

interface

private module function get_column_index(this, name)

1-based index of name in this%col; error stops if name is not found.

Arguments

Return Value integer

interface

private module function is_column_set(this, name)

Whether name is currently enabled to be written (its col(:)%is_set); error stops if name is not found (via get_column_index).

Arguments

Return Value logical

interface

private module function get_num_fields(this)

Total number of fields defined in this column_info, in maml source order, with no filtering by is_set/is_deactivated -- i.e. every field that was ever declared (via a fields: entry or %add_field).

Arguments

Return Value integer

interface

private module subroutine get_field_name(this, index, name)

Name of the field at the given 1-based position in maml source order (same order get_num_fields counts). index must be between 1 and get_num_fields(this); anything outside that range fails with error stop.

Arguments

interface

private module subroutine get_field_by_name(this, name, data_type, unit, info, ucd, array_size, col_size, qc_min, qc_max, qc_miss)

Reads back name's full field definition -- the same shape of values %add_field accepts, so a caller can inspect an already-parsed schema's columns or feed the result straight into another schema's %add_field (see %add_field_from, parquet_schema's own convenience wrapper built on top of this). Every output is optional/intent(out); pass only the ones you need. qc_min/qc_max are reconstructed as a single operator-prefixed string (e.g. ">= 5.0"), re-feedable into %add_field's own qc_min/qc_max arguments -- note this always carries an explicit operator, even if the original %add_field call left it implicit (">=" for min, "<=" for max), which is semantically identical but not necessarily byte-identical to the original input. qc_miss comes back as "Null" or "" (never "NA", even if that's what was originally declared -- both are equivalent aliases and the distinction isn't preserved in storage). Error stops if name is not found. Assumes this column_info reflects the schema's current fields: parquet_parse_maml (or, for a from-scratch schema, %init/%add_field followed by parquet_parse_maml) must already have run; any %add_field call since the last parse is not yet visible here.

Arguments

interface

private module subroutine get_field_by_index(this, index, name, data_type, unit, info, ucd, array_size, col_size, qc_min, qc_max, qc_miss)

Same as get_field_by_name, but looks the field up by its 1-based MAML source position (same order get_num_fields counts) instead of by name, additionally returning that field's name (always populated, not optional, since the caller doesn't already know it). index must be between 1 and get_num_fields(this); anything outside that range fails with error stop.

Arguments

private interface get_field_by_name()

Arguments

private interface get_field_by_index()

Arguments

interface

private module subroutine set_unavailable(this, name)

Backs parquet_schema%set_column_unavailable (see set_column_unavailable in the parquet_schema block above); disables name, or every non-deactivated column if name is absent. Error stops if name is a deactivated column.

Arguments

interface

private module subroutine set_available(this, name)

Backs parquet_schema%set_column_available; enables name, or every non-deactivated column if name is absent. Error stops if name is a deactivated column.

Arguments

interface

private module subroutine set_col_size(this, name, col_size, force)

Resolves name's col_size to col_size. Error stops if col_size < 1, if name is not found (via get_column_index), or if name's col_size is not currently "auto" and force is absent/.false. (pass force=.true. to override an already-resolved col_size too).

Arguments

interface

private module subroutine set_protected(this, name, protected)

Marks name Null-protected, or (protected=.false.) unmarks it -- the code-level equivalent of listing it under a MAML's extra: protected_cols:. A protected column may hold no Null at all: parquet_write_column error stops on an is_valid mask with any .false. entry, on a null date/time/timestamp element, and on an %append_null() in a parquet_string_column, and the column's Arrow field is written non-nullable.

Unprotecting a column that is currently protected is allowed -- a program may have a good reason to relax its own schema -- but emits a WARNING naming the column, since it overrides a declaration someone made deliberately. Never an abort. The warning does not depend on where the protection came from: a MAML's extra: protected_cols: and an earlier set_protected call in code are indistinguishable here, and both warn.

Error stops if name is not found. Call it before parquet_open_writer: the writer takes its copy of the schema at open time, so a later change has no effect on a writer that is already open.

Arguments

interface

private module subroutine set_array_size(this, name, array_size, force)

Resolves name's array_size to array_size. Error stops if array_size < 1, if name is not found, if name's data_type is not "string" (array_size only applies to string columns), or if name's array_size is not currently "auto" and force is absent/.false.

Arguments