diff --git a/minisql/src/schema.rs b/minisql/src/schema.rs index ba9759a..c56b4da 100644 --- a/minisql/src/schema.rs +++ b/minisql/src/schema.rs @@ -36,6 +36,24 @@ impl TableSchema { self.types[column_position] } + pub fn get_columns(&self) -> Vec<&ColumnName> { + self.column_name_position_mapping.iter().map(|(name, _)| name).collect() + } + + pub fn does_column_exist(&self, column_name: &ColumnName) -> bool { + self.column_name_position_mapping.contains_left(column_name) + } + + pub fn get_column_position(&self, column_name: &ColumnName) -> Option { + self.column_name_position_mapping.get_by_left(column_name).copied() + } + + pub fn get_type_at(&self, column_name: &ColumnName) -> Option { + let position = self.get_column_position(column_name)?; + self.types.get(position).copied() + } + + // TODO: Get rid of this after validation is merged fn get_column(&self, column_name: &ColumnName) -> DbResult<(DbType, ColumnPosition)> { match self.column_name_position_mapping.get_by_left(column_name) { Some(column_position) => match self.types.get(*column_position) { @@ -52,6 +70,7 @@ impl TableSchema { } } + // TODO: Get rid of this after validation is merged pub fn column_position_from_column_name( &self, column_name: &ColumnName, diff --git a/parser/src/validation.rs b/parser/src/validation.rs index 2be6dce..d978c0c 100644 --- a/parser/src/validation.rs +++ b/parser/src/validation.rs @@ -1,98 +1,107 @@ use std::collections::HashSet; -use minisql::{operation::{ColumnSelection, Condition, InsertionValues, Operation}, schema::TableSchema, type_system::{DbType, IndexableValue, Value}}; +use minisql::{operation::{ColumnSelection, Condition, InsertionValues, Operation}, schema::{TableSchema, ColumnName, TableName}, type_system::DbType}; #[derive(Debug)] pub enum ValidationError { - TableDoesNotExist(String), - TableExists(String), - ColumnDoesNotExist(String), - BadColumnPosition(usize), + TableDoesNotExist(TableName), + TableAlreadyExists(TableName), + ColumnsDoNotExist(Vec), DuplicateColumn(String), - TypeMismatch, - ValueForRequiredColumnIsMissing(String) + TypeMismatch(TypeMismatch), + RequiredColumnsAreMissing(Vec) } -pub fn type_of(value: &Value) -> DbType { - match value { - Value::Indexable(IndexableValue::Int(_)) => DbType::Int, - Value::Indexable(IndexableValue::String(_)) => DbType::String, - Value::Number(_) => DbType::Number, - Value::Indexable(IndexableValue::Uuid(_)) => DbType::Uuid - } +#[derive(Debug)] +pub struct TypeMismatch { + pub column_name: ColumnName, + pub received_type: DbType, + pub expected_type: DbType, } +pub type DbSchema<'a> = Vec<(TableName, &'a TableSchema)>; + /// Validates the operation based on db_metadata -pub fn validate_operation(operation: &Operation, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { +pub fn validate_operation(operation: &Operation, db_schema: &DbSchema) -> Result<(), ValidationError> { match operation { Operation::Select(table_name, column_selection, condition) => { - validate_select(table_name, column_selection, condition, db_metadata)?; + validate_select(table_name, column_selection, condition, db_schema)?; }, Operation::Insert(table_name, insertion_values) => { - validate_insert(&table_name, insertion_values, db_metadata)?; + validate_insert(&table_name, insertion_values, db_schema)?; }, Operation::Delete(table_name, condition) => { - validate_delete(table_name, condition, db_metadata)?; + validate_delete(table_name, condition, db_schema)?; }, // Operation::Update(table_name, insertion_values, condition) => { // validate_update(table_name, insertion_values, db_metadata)?; // }, Operation::CreateTable(table_name, schema) => { - validate_create(table_name, schema, db_metadata)?; + validate_create(table_name, schema, db_schema)?; }, Operation::CreateIndex(table_name, column_name) => { - validate_create_index(table_name, column_name, db_metadata)?; + validate_create_index(table_name, column_name, db_schema)?; }, // Operation::DropTable(table_name) => { - // validate_drop(table_name, db_metadata)?; + // validate_drop(table_name, db_schema)?; // } } Ok(()) } +fn validate_table_exists<'a>(db_schema: &DbSchema<'a>, table_name: &'a TableName) -> Result<&'a TableSchema, ValidationError> { + db_schema.iter().find(|(tname, _)| table_name.eq(tname)) + .ok_or(ValidationError::TableDoesNotExist(table_name.to_string())) + .map(|(_, table_schema)| table_schema).copied() +} + + // pub fn validate_drop(table_name: &str, db_metadata: &Vec<(String, TableSchema)>) -> Result<(), ValidationError> { // db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) // .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; // Ok(()) // } -pub fn validate_create(table_name: &str, schema: &TableSchema, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { - if db_metadata.iter().find(|(tname, _)| table_name.eq(tname)).is_some() { - return Err(ValidationError::TableExists(table_name.to_string())); - } - let mut column_names = HashSet::new(); - for (name, _) in &schema.column_name_position_mapping { - if column_names.contains(name) { - return Err(ValidationError::DuplicateColumn(name.clone())); - } else { - column_names.insert(name.clone()); - } +pub fn validate_create(table_name: &TableName, schema: &TableSchema, db_schema: &DbSchema) -> Result<(), ValidationError> { + if let Some(_) = get_table_schema(db_schema, table_name) { + return Err(ValidationError::TableAlreadyExists(table_name.to_string())); } + find_first_duplicate(&schema.get_columns()) + .map_or_else( + || Ok(()), + |duplicate_column| Err(ValidationError::DuplicateColumn(duplicate_column.to_string())) + )?; + // TODO: Ensure it has a primary key?? Ok(()) } -pub fn validate_select(table_name: &str, column_selection: &ColumnSelection, condition: &Option, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { - let (_, schema) = db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) - .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; +pub fn validate_select(table_name: &TableName, column_selection: &ColumnSelection, condition: &Option, db_schema: &Vec<(TableName, &TableSchema)>) -> Result<(), ValidationError> { + let schema = validate_table_exists(db_schema, table_name)?; match column_selection { ColumnSelection::Columns(columns) => { - columns.iter().find(|c| { - !schema.column_name_position_mapping.contains_left(*c) - }).map_or_else(||Ok(()), |c| Err(ValidationError::ColumnDoesNotExist(c.to_string())))?; + let non_existant_columns: Vec = + columns.iter().filter_map(|column| + if schema.does_column_exist(&column) { + Some(column.clone()) + } else { + None + }).collect(); + if non_existant_columns.len() > 0 { + Err(ValidationError::ColumnsDoNotExist(non_existant_columns)) + } else { + validate_condition(condition, schema) + } } - _ => {} + ColumnSelection::All => Ok(()) } - validate_condition(condition, schema)?; - Ok(()) } // pub fn validate_update(table_name: &str, insertion_values: &InsertionValues, db_metadata: &Vec<(String, TableSchema)>) -> Result<(), ValidationError> { -// let (_, schema) = db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) -// .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; +// let schema = validate_table_exists(db_schema, table_name)?; // let mut column_names = HashSet::new(); // // Find duplicate columns // for (name, _) in insertion_values { @@ -111,7 +120,7 @@ pub fn validate_select(table_name: &str, column_selection: &ColumnSelection, con // if let Some((name, _, _)) = column_value_type.iter().find(|(_, _, t)| { // t.is_none() // }) { -// return Err(ValidationError::ColumnDoesNotExist((*name).clone())); +// return Err(ValidationError::ColumnsDoNotExist(vec![(*name).clone())]); // } // // Check types @@ -128,63 +137,56 @@ pub fn validate_select(table_name: &str, column_selection: &ColumnSelection, con // Ok(()) // } -pub fn validate_insert(table_name: &str, insertion_values: &InsertionValues, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { - let (_, schema) = db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) - .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; - let inserted_columns: HashSet = HashSet::from_iter(insertion_values.iter().map(|(name, _)| name.clone())); - // TODO: primary key is not required - for (column_name, _) in &schema.column_name_position_mapping { - if !inserted_columns.contains(column_name) { - return Err(ValidationError::ValueForRequiredColumnIsMissing(column_name.clone())) - } +pub fn validate_insert(table_name: &TableName, insertion_values: &InsertionValues, db_schema: &DbSchema) -> Result<(), ValidationError> { + let schema = validate_table_exists(db_schema, table_name)?; + + // Check for duplicate columns in insertion_values. + let columns_in_query_vec: Vec<&ColumnName> = insertion_values.iter().map(|(column_name, _)| column_name).collect(); + find_first_duplicate(&columns_in_query_vec) + .map_or_else( + || Ok(()), + |duplicate_column| Err(ValidationError::DuplicateColumn(duplicate_column.to_string())) + )?; + + // Check that the set of columns in the insertion_values is the same as the set of required columns of the table. + let columns_in_query: HashSet<&ColumnName> = HashSet::from_iter(columns_in_query_vec); + let columns_in_schema: HashSet<&ColumnName> = HashSet::from_iter(schema.get_columns()); + let non_existant_columns = Vec::from_iter(columns_in_query.difference(&columns_in_schema)); + if non_existant_columns.len() > 0 { + return Err(ValidationError::ColumnsDoNotExist(non_existant_columns.iter().map(|str| str.to_string()).collect())); } - // Ensure columns exist in schema - let column_value_type: Vec<_> = insertion_values.iter().map(|(column, value)| { - (column, value, schema.column_name_position_mapping.iter().find(|(name, _) | { - (*name).eq(column) - }).map(|(_, t)| schema.types.get(*t as usize))) - }).collect(); - if let Some((name, _, _)) = column_value_type.iter().find(|(_, _, t)| { - match t { - Some(Some(_)) => false, - _ => true - } - }) { - return Err(ValidationError::ColumnDoesNotExist((*name).clone())); + let missing_required_columns = Vec::from_iter(columns_in_schema.difference(&columns_in_query)); + if missing_required_columns.len() > 0 { + return Err(ValidationError::RequiredColumnsAreMissing(missing_required_columns.iter().map(|str| str.to_string()).collect())); } // Check types - if let Some((_, _, _)) = column_value_type.iter().find(|(_, value, t)| { - if let Some(Some(t)) = t { - !type_of(value).eq(t) - } else { - false + for (column_name, value) in insertion_values { + let expected_type = schema.get_type_at(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(TypeMismatch { column_name: column_name.to_string(), received_type: value_type, expected_type })); } - }) { - // TODO: Add column name information - return Err(ValidationError::TypeMismatch); } + Ok(()) } -pub fn validate_delete(table_name: &str, condition: &Option, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { - let (_, schema) = db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) - .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; +pub fn validate_delete(table_name: &TableName, condition: &Option, db_schema: &DbSchema) -> Result<(), ValidationError> { + let schema = validate_table_exists(db_schema, table_name)?; validate_condition(condition, schema)?; Ok(()) } fn validate_condition(condition: &Option, schema: &TableSchema) -> Result<(), ValidationError> { match condition { - Some(c) => { - match c { - Condition::Eq(left, right) => { - let position = schema.column_name_position_mapping.get_by_left(left) - .ok_or(ValidationError::ColumnDoesNotExist(left.clone()))?; - let column_type = schema.types.get(*position as usize) - .ok_or(ValidationError::BadColumnPosition(*position))?; - if !column_type.eq(&type_of(right)) { - return Err(ValidationError::TypeMismatch); + Some(condition) => { + match condition { + Condition::Eq(column_name, value) => { + let expected_type: DbType = schema.get_type_at(column_name).ok_or(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()]))?; + let value_type: DbType = value.to_type(); + if !expected_type.eq(&value_type) { + return Err(ValidationError::TypeMismatch(TypeMismatch { column_name: column_name.to_string(), received_type: value_type, expected_type })); } } } @@ -194,13 +196,31 @@ fn validate_condition(condition: &Option, schema: &TableSchema) -> Re Ok(()) } -fn validate_create_index(table_name: &str, column_name: &str, db_metadata: &Vec<(String, &TableSchema)>) -> Result<(), ValidationError> { - // Ensure table exists - let (_, schema) = db_metadata.iter().find(|(tname, _)| table_name.eq(tname)) - .ok_or(ValidationError::TableDoesNotExist(table_name.to_string()))?; - // Ensure column exists - if !schema.column_name_position_mapping.contains_left(column_name) { - return Err(ValidationError::ColumnDoesNotExist(column_name.to_string())); +fn validate_create_index(table_name: &TableName, column_name: &ColumnName, db_schema: &DbSchema) -> Result<(), ValidationError> { + let schema = validate_table_exists(db_schema, table_name)?; + if schema.does_column_exist(column_name) { + Ok(()) + } else { + Err(ValidationError::ColumnsDoNotExist(vec![column_name.to_string()])) } - Ok(()) -} \ No newline at end of file +} + +// ===Helpers=== +fn find_first_duplicate(xs: &[A]) -> Option<&A> +where A: Eq + std::hash::Hash +{ + let mut already_seen_elements: HashSet<&A> = HashSet::new(); + for x in xs { + if already_seen_elements.contains(x) { + return Some(x); + } else { + already_seen_elements.insert(&x); + } + } + None +} + +fn get_table_schema<'a>(db_schema: &DbSchema<'a>, table_name: &'a TableName) -> Option<&'a TableSchema> { + let (_, table_schema) = db_schema.iter().find(|(tname, _)| table_name.eq(tname))?; + Some(table_schema) +}