common/schema: use a symbol to identify columns

common/schema/root.go

@@ -1,42 +0,0 @@
-// SPDX-FileCopyrightText: 2022 Free Mobile
-// SPDX-License-Identifier: AGPL-3.0-only
-
-// Package schema is an abstraction of the data schema used by Akvorado. It is a
-// leaky abstraction as there are multiple parts dependant of the subsystem that
-// will use it.
-package schema
-
-import orderedmap "github.com/elliotchance/orderedmap/v2"
-
-// Schema is the data schema.
-type Schema struct {
-	// We use an ordered map for direct access to columns.
-	Columns *orderedmap.OrderedMap[string, Column]
-
-	// For ClickHouse. This is the set of primary keys (order is important and
-	// may not follow column order).
-	ClickHousePrimaryKeys []string
-}
-
-// Column represents a column of data.
-type Column struct {
-	Name     string
-	MainOnly bool
-
-	// For ClickHouse. `NotSortingKey' is for columns generated from other
-	// columns. It is only useful if not MainOnly and not Alias. `GenerateFrom'
-	// is for a column that's generated from an SQL expression instead of being
-	// retrieved from the protobuf. `TransformFrom' and `TransformTo' work in
-	// pairs. The first one is the set of column in the raw table while the
-	// second one is how to transform it for the main table.
-	ClickHouseType          string
-	ClickHouseCodec         string
-	ClickHouseAlias         string
-	ClickHouseNotSortingKey bool
-	ClickHouseGenerateFrom  string
-	ClickHouseTransformFrom []Column
-	ClickHouseTransformTo   string
-
-	// For the console.
-	ConsoleNotDimension bool
-}