ColumnName ~> Column

minisql/src/internals/row.rs

@@ -5,7 +5,7 @@ use std::slice::SliceIndex;
 use serde::{Deserialize, Serialize};
 use crate::restricted_row::RestrictedRow;
 
-pub type ColumnPosition = usize;
+pub type Column = usize;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Row(Vec<Value>);
@@ -61,13 +61,13 @@ impl Row {
         self.0.len()
     }
 
-    pub fn get(&self, column: ColumnPosition) -> Option<&Value> {
+    pub fn get(&self, column: Column) -> Option<&Value> {
         self.0.get(column)
     }
 
-    pub fn restrict_columns(&self, columns: &Vec<ColumnPosition>) -> RestrictedRow {
+    pub fn restrict_columns(&self, columns: &Vec<Column>) -> RestrictedRow {
         // If the index from `columns` is non-existant in `row`, it will just ignore it.
-        let mut subrow: Vec<(ColumnPosition, Value)> = vec![];
+        let mut subrow: Vec<(Column, Value)> = vec![];
         for column in columns {
             if let Some(value) = self.get(*column) {
                 subrow.push((*column, value.clone()));

minisql/src/internals/table.rs

@@ -3,7 +3,7 @@ use serde::{Deserialize, Serialize};
 
 use crate::error::RuntimeError;
 use crate::internals::column_index::ColumnIndex;
-use crate::internals::row::{ColumnPosition, Row};
+use crate::internals::row::{Column, Row};
 use crate::restricted_row::RestrictedRow;
 use crate::schema::{ColumnName, TableSchema, TableName};
 use crate::result::DbResult;
@@ -14,7 +14,7 @@ pub struct Table {
     schema: TableSchema,
     rows: Rows, // TODO: Consider wrapping this in a lock. Also consider if we need to have the
     // same lock for both rows and indexes
-    indexes: HashMap<ColumnPosition, ColumnIndex>,
+    indexes: HashMap<Column, ColumnIndex>,
 }
 
 pub type Rows = BTreeMap<Uuid, Row>;
@@ -36,7 +36,7 @@ impl Table {
         &self.rows
     }
 
-    pub fn indexes(&self) -> &HashMap<ColumnPosition, ColumnIndex> {
+    pub fn indexes(&self) -> &HashMap<Column, ColumnIndex> {
         &self.indexes
     }
 
@@ -55,7 +55,7 @@ impl Table {
             .collect()
     }
 
-    fn get_rows_by_value(&self, column: ColumnPosition, value: &Value) -> Vec<Row> {
+    fn get_rows_by_value(&self, column: Column, value: &Value) -> Vec<Row> {
         // brute-force search
         self.rows
             .values()
@@ -69,7 +69,7 @@ impl Table {
             .collect()
     }
 
-    pub fn select_all_rows<'a>(&'a self, selected_columns: Vec<ColumnPosition>) -> impl Iterator<Item=RestrictedRow> + 'a {
+    pub fn select_all_rows<'a>(&'a self, selected_columns: Vec<Column>) -> impl Iterator<Item=RestrictedRow> + 'a {
         self.rows
             .values()
             .map(move |row| row.restrict_columns(&selected_columns))
@@ -77,8 +77,8 @@ impl Table {
 
     pub fn select_rows_where_eq<'a>(
         &'a self,
-        selected_columns: Vec<ColumnPosition>,
+        selected_columns: Vec<Column>,
-        column: ColumnPosition,
+        column: Column,
         value: Value,
     ) -> DbResult<impl Iterator<Item=RestrictedRow> + 'a> {
         let restrict_columns_of_row = move |row: Row| row.restrict_columns(&selected_columns);
@@ -149,7 +149,7 @@ impl Table {
         total_count
     }
 
-    fn delete_rows_by_value(&mut self, column: ColumnPosition, value: &Value) -> usize {
+    fn delete_rows_by_value(&mut self, column: Column, value: &Value) -> usize {
         let matched_ids: HashSet<Uuid> = self
             .rows
             .iter()
@@ -173,7 +173,7 @@ impl Table {
 
     pub fn delete_rows_where_eq(
         &mut self,
-        column: ColumnPosition,
+        column: Column,
         value: Value,
     ) -> DbResult<usize> {
         match value {
@@ -186,7 +186,7 @@ impl Table {
     }
 
     // ======Indexing======
-    pub fn attach_index(&mut self, column: ColumnPosition) -> DbResult<()> {
+    pub fn attach_index(&mut self, column: Column) -> DbResult<()> {
         if self.indexes.get(&column).is_some() {
             let column_name = self.schema.column_name_from_column(column).clone();
             let table_name = self.schema.table_name().clone();
@@ -200,7 +200,7 @@ impl Table {
 
     fn fetch_ids_from_index(
         &self,
-        column: ColumnPosition,
+        column: Column,
         value: &IndexableValue,
     ) -> DbResult<Option<HashSet<Uuid>>> {
         if self.schema.is_primary(column) {
@@ -228,7 +228,7 @@ impl Table {
 fn update_index_from_table(
     column_index: &mut ColumnIndex,
     table: &Table,
-    column: ColumnPosition,
+    column: Column,
 ) -> DbResult<()> {
     for (id, row) in &table.rows {
         let value = match &row[column] {
@@ -237,7 +237,6 @@ fn update_index_from_table(
                 let column_name: ColumnName = table
                     .schema
                     .column_name_from_column(column);
-                // TODO: Perhaps this should be handled in validation?
                 return Err(RuntimeError::AttemptToIndexNonIndexableColumn(
                     table.table_name().to_string(),
                     column_name,

minisql/src/interpreter.rs

@@ -1,4 +1,4 @@
-use crate::internals::row::ColumnPosition;
+use crate::internals::row::Column;
 use crate::schema::{TableName, TableSchema};
 use crate::internals::table::Table;
 use crate::operation::{Operation, Condition};
@@ -145,7 +145,7 @@ impl State {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::internals::row::ColumnPosition;
+    use crate::internals::row::Column;
     use std::collections::HashSet;
     use crate::type_system::{DbType, IndexableValue, Value};
     use crate::operation::Operation;
@@ -259,8 +259,8 @@ mod tests {
         let users_schema = users_schema();
         let users_position: TablePosition = 0;
 
-        let id_column: ColumnPosition = 0;
+        let id_column: Column = 0;
-        let name_column: ColumnPosition = 1;
+        let name_column: Column = 1;
 
         state
             .interpret(CreateTable(users_schema.clone()))
@@ -377,7 +377,7 @@ mod tests {
         let users_schema = users_schema();
         let users_position: TablePosition = 0;
 
-        let id_column: ColumnPosition = 0;
+        let id_column: Column = 0;
 
         state
             .interpret(CreateTable(users_schema.clone()))
@@ -451,7 +451,7 @@ mod tests {
         let users_schema = users_schema();
         let users_position: TablePosition = 0;
 
-        let name_column: ColumnPosition = 1;
+        let name_column: Column = 1;
 
         state
             .interpret(CreateTable(users_schema.clone()))
@@ -497,7 +497,7 @@ mod tests {
         let table = &state.tables[0];
         assert!(table.rows().len() == 2);
 
-        let user: ColumnPosition = 1;
+        let user: Column = 1;
         assert!(table.indexes().contains_key(&user));
 
         let index = table.indexes().get(&user).unwrap();
@@ -519,8 +519,8 @@ pub fn example() {
     use Operation::*;
     use Value::*;
 
-    let id_column: ColumnPosition = 0;
+    let id_column: Column = 0;
-    let name_column: ColumnPosition = 1;
+    let name_column: Column = 1;
     // let age_column: ColumnPosition = 2;
 
     let users_schema: TableSchema = {

minisql/src/operation.rs

@@ -1,6 +1,6 @@
 use crate::schema::TableSchema;
 use crate::type_system::Value;
-use crate::internals::row::ColumnPosition;
+use crate::internals::row::Column;
 use crate::interpreter::TablePosition;
 
 // Validated operation. Constructed by validation crate.
@@ -10,15 +10,15 @@ pub enum Operation {
     Insert(TablePosition, InsertionValues),
     Delete(TablePosition, Option<Condition>),
     CreateTable(TableSchema),
-    CreateIndex(TablePosition, ColumnPosition),
+    CreateIndex(TablePosition, Column),
 }
 
 // Assumes that these are sorted by column position.
 pub type InsertionValues = Vec<Value>;
 
-pub type ColumnSelection = Vec<ColumnPosition>;
+pub type ColumnSelection = Vec<Column>;
 
 #[derive(Debug, PartialEq)]
 pub enum Condition {
-    Eq(ColumnPosition, Value),
+    Eq(Column, Value),
 }

minisql/src/restricted_row.rs

@@ -1,14 +1,14 @@
 use std::ops::Index;
 use std::slice::SliceIndex;
-use crate::internals::row::ColumnPosition;
+use crate::internals::row::Column;
 use crate::type_system::Value;
 
 #[derive(Debug, Clone)]
-pub struct RestrictedRow(Vec<(ColumnPosition, Value)>);
+pub struct RestrictedRow(Vec<(Column, Value)>);
 
 impl<Idx> Index<Idx> for RestrictedRow
 where
-    Idx: SliceIndex<[(ColumnPosition, Value)]>,
+    Idx: SliceIndex<[(Column, Value)]>,
 {
     type Output = Idx::Output;
 
@@ -17,8 +17,8 @@ where
     }
 }
 
-impl From<Vec<(ColumnPosition, Value)>> for RestrictedRow {
+impl From<Vec<(Column, Value)>> for RestrictedRow {
-    fn from(v: Vec<(ColumnPosition, Value)>) -> Self {
+    fn from(v: Vec<(Column, Value)>) -> Self {
         RestrictedRow(v)
     }
 }
@@ -28,7 +28,7 @@ impl RestrictedRow {
         self.0.len()
     }
 
-    pub fn iter(&self) -> impl Iterator<Item=&(ColumnPosition, Value)> {
+    pub fn iter(&self) -> impl Iterator<Item=&(Column, Value)> {
         self.0.iter()
     }
 }

minisql/src/schema.rs

@@ -1,4 +1,4 @@
-use crate::internals::row::{ColumnPosition, Row};
+use crate::internals::row::{Column, Row};
 use crate::operation::{InsertionValues, ColumnSelection};
 use crate::result::DbResult;
 use crate::type_system::{DbType, IndexableValue, Uuid, Value};
@@ -10,8 +10,8 @@ use serde::{Deserialize, Serialize};
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct TableSchema {
     table_name: TableName, // used for descriptive errors
-    primary_key: ColumnPosition,
+    primary_key: Column,
-    column_name_position_mapping: BiMap<ColumnName, ColumnPosition>,
+    column_name_position_mapping: BiMap<ColumnName, Column>,
     types: Vec<DbType>,
 }
 
@@ -20,11 +20,11 @@ pub type ColumnName = String;
 
 impl TableSchema {
     pub fn new(table_name: TableName, primary_column_name: ColumnName, columns: Vec<ColumnName>, types: Vec<DbType>) -> Self {
-        let mut column_name_position_mapping: BiMap<ColumnName, ColumnPosition> = BiMap::new();
+        let mut column_name_position_mapping: BiMap<ColumnName, Column> = BiMap::new();
         for (column, column_name) in columns.into_iter().enumerate() {
             column_name_position_mapping.insert(column_name, column);
         }
-        let primary_key: ColumnPosition = match column_name_position_mapping.get_by_left(&primary_column_name).copied() {
+        let primary_key: Column = match column_name_position_mapping.get_by_left(&primary_column_name).copied() {
             Some(primary_key) => primary_key,
             None => unreachable!() // SAFETY: Existence of unique primary key is ensured in validation.
         };
@@ -35,7 +35,7 @@ impl TableSchema {
         &self.table_name
     }
 
-    pub fn column_type(&self, column: ColumnPosition) -> DbType {
+    pub fn column_type(&self, column: Column) -> DbType {
         self.types[column]
     }
 
@@ -47,7 +47,7 @@ impl TableSchema {
         self.column_name_position_mapping.contains_left(column_name)
     }
 
-    pub fn get_column_position(&self, column_name: &ColumnName) -> Option<ColumnPosition> {
+    pub fn get_column_position(&self, column_name: &ColumnName) -> Option<Column> {
         self.column_name_position_mapping.get_by_left(column_name).copied()
     }
 
@@ -57,7 +57,7 @@ impl TableSchema {
         selection
     }
 
-    pub fn get_column(&self, column_name: &ColumnName) -> Option<(ColumnPosition, DbType)> {
+    pub fn get_column(&self, column_name: &ColumnName) -> Option<(Column, DbType)> {
         let column = self.get_column_position(column_name)?;
         Some((column, self.column_type(column)))
     }
@@ -67,12 +67,12 @@ impl TableSchema {
         self.types.get(position).copied()
     }
 
-    pub fn is_primary(&self, column: ColumnPosition) -> bool {
+    pub fn is_primary(&self, column: Column) -> bool {
         self.primary_key == column
     }
 
     // Assumes `column` comes from a validated source.
-    pub fn column_name_from_column(&self, column: ColumnPosition) -> ColumnName {
+    pub fn column_name_from_column(&self, column: Column) -> ColumnName {
         match self
             .column_name_position_mapping
             .get_by_right(&column)