Cannot accumulate empty arrays

graphile · Feb 28, 2025 · 9570419 · 9570419
1 parent 65d85cc
commit 9570419
Showing 1 changed file with 8 additions and 3 deletions.
diff --git a/grafast/dataplan-pg/src/steps/pgSelect.ts b/grafast/dataplan-pg/src/steps/pgSelect.ts
@@ -3699,9 +3699,14 @@ function buildJoin(inJoins: readonly PgSelectPlanJoin[]) {
 
 function buildSelect(selects: readonly SQL[], asArray = false) {
   if (asArray) {
-    return sql`select array[\n${sql.indent(
-      sql.join(selects, ",\n"),
-    )}\n]::text[]`;
+    if (selects.length < 1) {
+      // Cannot accumulate empty arrays
+      return sql`select array[null]::text[]`;
+    } else {
+      return sql`select array[\n${sql.indent(
+        sql.join(selects, ",\n"),
+      )}\n]::text[]`;
+    }
   }
   const fragmentsWithAliases = selects.map(
     (frag, idx) => sql`${frag} as ${sql.identifier(String(idx))}`,