store: pass list of indexes when pruning a subgraph

Author: shiyasmohd

store/postgres/src/relational/index.rs

@@ -734,6 +734,16 @@ pub struct IndexList {
     pub(crate) indexes: HashMap<String, Vec<CreateIndex>>,
 }
 
+pub fn load_indexes_from_table(
+    conn: &mut PgConnection,
+    table: &Arc<Table>,
+    schema_name: &str,
+) -> Result<Vec<CreateIndex>, StoreError> {
+    let table_name = table.name.as_str();
+    let indexes = catalog::indexes_for_table(conn, schema_name, table_name)?;
+    Ok(indexes.into_iter().map(CreateIndex::parse).collect())
+}
+
 impl IndexList {
     pub fn load(
         conn: &mut PgConnection,
@@ -746,10 +756,8 @@ impl IndexList {
         let schema_name = site.namespace.clone();
         let layout = store.layout(conn, site)?;
         for (_, table) in &layout.tables {
-            let table_name = table.name.as_str();
-            let indexes = catalog::indexes_for_table(conn, schema_name.as_str(), table_name)?;
-            let collect: Vec<CreateIndex> = indexes.into_iter().map(CreateIndex::parse).collect();
-            list.indexes.insert(table_name.to_string(), collect);
+            let indexes = load_indexes_from_table(conn, table, schema_name.as_str())?;
+            list.indexes.insert(table.name.to_string(), indexes);
         }
         Ok(list)
     }

store/postgres/src/relational/prune.rs

@@ -1,4 +1,4 @@
-use std::{fmt::Write, sync::Arc, time::Instant};
+use std::{collections::HashMap, fmt::Write, sync::Arc, time::Instant};
 
 use diesel::{
     connection::SimpleConnection,
@@ -24,7 +24,10 @@ use crate::{
     relational::{Table, VID_COLUMN},
 };
 
-use super::{Catalog, Layout, Namespace};
+use super::{
+    index::{load_indexes_from_table, IndexList},
+    Catalog, Layout, Namespace,
+};
 
 // Additions to `Table` that are useful for pruning
 impl Table {
@@ -94,9 +97,15 @@ impl TablePair {
         if catalog::table_exists(conn, dst_nsp.as_str(), &dst.name)? {
             writeln!(query, "truncate table {};", dst.qualified_name)?;
         } else {
+            let mut list = IndexList {
+                indexes: HashMap::new(),
+            };
+            let indexes = load_indexes_from_table(conn, &src, dst_nsp.as_str())?;
+            list.indexes.insert(src.name.to_string(), indexes);
+
             // In case of pruning we don't do delayed creation of indexes,
             // as the asumption is that there is not that much data inserted.
-            dst.as_ddl(schema, catalog, None, &mut query)?;
+            dst.as_ddl(schema, catalog, Some(&list), &mut query)?;
         }
         conn.batch_execute(&query)?;