refactor: remove optional from the protos (#756)

src/sql/src/statements.rs

@@ -283,7 +283,7 @@ pub fn sql_column_def_to_grpc_column_def(col: ColumnDef) -> Result<api::v1::Colu
         name,
         datatype: data_type,
         is_nullable,
-        default_constraint,
+        default_constraint: default_constraint.unwrap_or_default(),
     })
 }
 
@@ -588,7 +588,7 @@ mod tests {
         assert_eq!("col", grpc_column_def.name);
         assert!(grpc_column_def.is_nullable); // nullable when options are empty
         assert_eq!(ColumnDataType::Float64 as i32, grpc_column_def.datatype);
-        assert_eq!(None, grpc_column_def.default_constraint);
+        assert!(grpc_column_def.default_constraint.is_empty());
 
         // test not null
         let column_def = ColumnDef {

src/sql/src/statements/alter.rs

@@ -56,7 +56,7 @@ impl TryFrom<AlterTable> for AlterExpr {
     type Error = crate::error::Error;
 
     fn try_from(value: AlterTable) -> Result<Self, Self::Error> {
-        let (catalog, schema, table) = table_idents_to_full_name(&value.table_name)?;
+        let (catalog_name, schema_name, table_name) = table_idents_to_full_name(&value.table_name)?;
 
         let kind = match value.alter_operation {
             AlterTableOperation::AddConstraint(_) => {
@@ -80,9 +80,9 @@ impl TryFrom<AlterTable> for AlterExpr {
             }
         };
         let expr = AlterExpr {
-            catalog_name: Some(catalog),
-            schema_name: Some(schema),
-            table_name: table,
+            catalog_name,
+            schema_name,
+            table_name,
             kind: Some(kind),
         };