Move Column into schema.rs

DESIGN.md

@@ -136,7 +136,7 @@ struct TableMetaData {
     columns: Vec<(ColumnName, DbType, ColumnPosition)>
 }
 
-fn column_position(TableMetaData, ColumnName) -> ColumnPosition
+fn column(TableMetaData, ColumnName) -> ColumnPosition
 
 struct Table {
     meta: TableMetaData,

minisql/src/internals/row.rs

@@ -4,8 +4,7 @@ use std::ops::{Index, IndexMut};
 use std::slice::SliceIndex;
 use serde::{Deserialize, Serialize};
 use crate::restricted_row::RestrictedRow;
-
+use crate::schema::Column;
-pub type Column = usize;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Row(Vec<Value>);

minisql/src/internals/table.rs

@@ -3,9 +3,9 @@ use serde::{Deserialize, Serialize};
 
 use crate::error::RuntimeError;
 use crate::internals::column_index::ColumnIndex;
-use crate::internals::row::{Column, Row};
+use crate::internals::row::Row;
 use crate::restricted_row::RestrictedRow;
-use crate::schema::{ColumnName, TableSchema, TableName};
+use crate::schema::{Column, ColumnName, TableSchema, TableName};
 use crate::result::DbResult;
 use crate::type_system::{IndexableValue, Uuid, Value};
 

minisql/src/interpreter.rs

@@ -1,5 +1,4 @@
-use crate::internals::row::Column;
+use crate::schema::{Column, TableName, TableSchema};
-use crate::schema::{TableName, TableSchema};
 use crate::internals::table::Table;
 use crate::operation::{Operation, Condition};
 use crate::result::DbResult;
@@ -145,7 +144,7 @@ impl State {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::internals::row::Column;
+    use crate::schema::Column;
     use std::collections::HashSet;
     use crate::type_system::{DbType, IndexableValue, Value};
     use crate::operation::Operation;

minisql/src/operation.rs

@@ -1,6 +1,5 @@
-use crate::schema::TableSchema;
+use crate::schema::{Column, TableSchema};
 use crate::type_system::Value;
-use crate::internals::row::Column;
 use crate::interpreter::TablePosition;
 
 // Validated operation. Constructed by validation crate.

minisql/src/restricted_row.rs

@@ -1,6 +1,6 @@
 use std::ops::Index;
 use std::slice::SliceIndex;
-use crate::internals::row::Column;
+use crate::schema::Column;
 use crate::type_system::Value;
 
 #[derive(Debug, Clone)]

minisql/src/schema.rs

@@ -1,4 +1,4 @@
-use crate::internals::row::{Column, Row};
+use crate::internals::row::Row;
 use crate::operation::{InsertionValues, ColumnSelection};
 use crate::result::DbResult;
 use crate::type_system::{DbType, IndexableValue, Uuid, Value};
@@ -17,6 +17,8 @@ pub struct TableSchema {
 
 pub type TableName = String;
 pub type ColumnName = String;
+pub type Column = usize;
+
 
 impl TableSchema {
     pub fn new(table_name: TableName, primary_column_name: ColumnName, columns: Vec<ColumnName>, types: Vec<DbType>) -> Self {
@@ -47,7 +49,7 @@ impl TableSchema {
         self.column_name_position_mapping.contains_left(column_name)
     }
 
-    pub fn get_column_position(&self, column_name: &ColumnName) -> Option<Column> {
+    pub fn get_column(&self, column_name: &ColumnName) -> Option<Column> {
         self.column_name_position_mapping.get_by_left(column_name).copied()
     }
 
@@ -57,13 +59,13 @@ impl TableSchema {
         selection
     }
 
-    pub fn get_column(&self, column_name: &ColumnName) -> Option<(Column, DbType)> {
+    pub fn get_typed_column(&self, column_name: &ColumnName) -> Option<(Column, DbType)> {
-        let column = self.get_column_position(column_name)?;
+        let column = self.get_column(column_name)?;
         Some((column, self.column_type(column)))
     }
 
     pub fn get_type_at(&self, column_name: &ColumnName) -> Option<DbType> {
-        let position = self.get_column_position(column_name)?;
+        let position = self.get_column(column_name)?;
         self.types.get(position).copied()
     }
 

parser/src/validation.rs

@@ -122,7 +122,7 @@ fn validate_select(table_name: TableName, column_selection: syntax::ColumnSelect
                 Err(ValidationError::ColumnsDoNotExist(non_existant_columns))
             } else {
                 let selection: operation::ColumnSelection =
-                    columns.iter().filter_map(|column_name| schema.get_column_position(column_name)).collect();
+                    columns.iter().filter_map(|column_name| schema.get_column(column_name)).collect();
                 let validated_condition = validate_condition(condition, schema)?;
                 Ok(Operation::Select(table_position, selection, validated_condition))
             }
@@ -163,7 +163,7 @@ fn validate_insert(table_name: TableName, insertion_values: syntax::InsertionVal
                                                               // to get the values in a vector
                                                               // sorted by the key.
     for (column_name, value) in insertion_values {
-        let (column, expected_type) = schema.get_column(&column_name).ok_or(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()]))?; // By the previous validation steps this is never gonna trigger an error.
+        let (column, expected_type) = schema.get_typed_column(&column_name).ok_or(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()]))?; // By the previous validation steps this is never gonna trigger an error.
         let value_type = value.to_type();
         if value_type != expected_type {
             return Err(ValidationError::TypeMismatch { column_name: column_name.to_string(), received_type: value_type, expected_type });
@@ -189,7 +189,7 @@ fn validate_condition(condition: Option<syntax::Condition>, schema: &TableSchema
         Some(condition) => {
             match condition {
                 syntax::Condition::Eq(column_name, value) => {
-                    let (column, expected_type) = schema.get_column(&column_name).ok_or(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()]))?;
+                    let (column, expected_type) = schema.get_typed_column(&column_name).ok_or(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()]))?;
                     let value_type: DbType = value.to_type();
                     if expected_type.eq(&value_type) {
                         Ok(Some(operation::Condition::Eq(column, value)))
@@ -206,7 +206,7 @@ fn validate_condition(condition: Option<syntax::Condition>, schema: &TableSchema
 fn validate_create_index(table_name: TableName, column_name: ColumnName, db_schema: &DbSchema) -> Result<Operation, ValidationError> {
     let (table_position, schema) = validate_table_exists(db_schema, &table_name)?;
     schema
-        .get_column(&column_name)
+        .get_typed_column(&column_name)
         .map_or_else(
             || Err(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()])),
             |(column, type_)| {

server/src/proto_wrapper.rs

@@ -1,7 +1,7 @@
 use async_trait::async_trait;
 use minisql::restricted_row::RestrictedRow;
-use minisql::schema::TableSchema;
+use minisql::schema::{Column, TableSchema};
-use minisql::type_system::{Value};
+use minisql::type_system::Value;
 use proto::message::backend::{BackendMessage, ColumnDescription, CommandCompleteData, DataRowData, ErrorResponseData, ReadyForQueryData, RowDescriptionData};
 use proto::message::primitive::pglist::PgList;
 use proto::writer::backend::BackendProtoWriter;
@@ -58,7 +58,7 @@ impl<W> ServerProto for W where W: BackendProtoWriter + Send {
 
     async fn write_table_header(&mut self, table_schema: &TableSchema, row: &RestrictedRow) -> anyhow::Result<()> {
         let columns = row.iter()
-            .map(|(index, value)| value_to_column_description(table_schema, value, *index))
+            .map(|(column, value)| value_to_column_description(table_schema, value, *column))
             .collect::<anyhow::Result<Vec<ColumnDescription>>>()?;
 
         self.write_proto(RowDescriptionData { columns: columns.into() }.into()).await?;
@@ -84,7 +84,7 @@ impl<W> ServerProto for W where W: BackendProtoWriter + Send {
     }
 }
 
-fn value_to_column_description(schema: &TableSchema, value: &Value, index: usize) -> anyhow::Result<ColumnDescription> {
+fn value_to_column_description(schema: &TableSchema, value: &Value, index: Column) -> anyhow::Result<ColumnDescription> {
     let name = schema.column_name_from_column(index);
 
     let table_oid = schema.table_name().as_bytes().as_ptr() as i32;