ui: show data when max size reached for schema insight

Previously, when the sql api returned a max size reached
error, we were just showing the error, but not the data
that was also being returned.

This commit updates the Insights Schema page
with the new behaviour.

The query to retrieve the drop recommendations was returning
all indexes and the ui was doing the filtering. This commit
also changes the query to only return the indexes with a
drop recommendation, resulting in a lot less data being sent
with the sql api and causing less size limit reached.
Then the ui just needs to decided the type of drop.

Part Of: cockroachdb#96184
Release note (ui change): Still show data on the console
(with a warning) for Schema Insights when we reach a
"max size exceed" error from the sql api.

pkg/ui/workspaces/cluster-ui/src/api/schemaInsightsApi.ts

@@ -14,7 +14,9 @@ import {
   executeInternalSql,
   LONG_TIMEOUT,
   sqlResultsAreEmpty,
-  sqlApiErrorMessage,
+  LARGE_RESULT_SIZE,
+  SqlApiResponse,
+  formatApiResult,
 } from "./sqlApi";
 import {
   InsightRecommendation,
@@ -128,23 +130,37 @@ function createIndexRecommendationsToSchemaInsight(
   return results;
 }
 
+// This query have an ORDER BY for the cases where we reach the limit of the sql-api
+// and want to return the most used ones as a priority.
 const dropUnusedIndexQuery: SchemaInsightQuery<ClusterIndexUsageStatistic> = {
   name: "DropIndex",
-  query: `SELECT
-            us.table_id,
-            us.index_id,
-            us.last_read,
-            ti.created_at,
-            ti.index_name,
-            t.name as table_name,
-            t.parent_id as database_id,
-            t.database_name,
-            t.schema_name,
-            (SELECT value FROM crdb_internal.cluster_settings WHERE variable = 'sql.index_recommendation.drop_unused_duration') AS unused_threshold
-          FROM "".crdb_internal.index_usage_statistics AS us
-                 JOIN "".crdb_internal.table_indexes as ti ON us.index_id = ti.index_id AND us.table_id = ti.descriptor_id
-                 JOIN "".crdb_internal.tables as t ON t.table_id = ti.descriptor_id and t.name = ti.descriptor_name
-          WHERE t.database_name != 'system' AND ti.index_type != 'primary';`,
+  query: `WITH cs AS (
+    SELECT value 
+        FROM crdb_internal.cluster_settings 
+    WHERE variable = 'sql.index_recommendation.drop_unused_duration'
+    )
+    SELECT * FROM (SELECT us.table_id,
+                          us.index_id,
+                          us.last_read,
+                          us.total_reads,
+                          ti.created_at,
+                          ti.index_name,
+                          t.name      as table_name,
+                          t.parent_id as database_id,
+                          t.database_name,
+                          t.schema_name,
+                          cs.value as unused_threshold,
+                          cs.value::interval as interval_threshold, 
+                          now() - COALESCE(us.last_read AT TIME ZONE 'UTC', COALESCE(ti.created_at, '0001-01-01')) as unused_interval
+                   FROM "".crdb_internal.index_usage_statistics AS us
+                            JOIN "".crdb_internal.table_indexes as ti
+                                 ON us.index_id = ti.index_id AND us.table_id = ti.descriptor_id
+                            JOIN "".crdb_internal.tables as t
+                                 ON t.table_id = ti.descriptor_id and t.name = ti.descriptor_name
+                            CROSS JOIN cs
+                   WHERE t.database_name != 'system' AND ti.index_type != 'primary')
+          WHERE unused_interval > interval_threshold
+          ORDER BY total_reads DESC;`,
   toSchemaInsight: clusterIndexUsageStatsToSchemaInsight,
 };
 
@@ -181,26 +197,22 @@ const schemaInsightQueries: SchemaInsightQuery<SchemaInsightResponse>[] = [
 
 // getSchemaInsights makes requests over the SQL API and transforms the corresponding
 // SQL responses into schema insights.
-export async function getSchemaInsights(): Promise<InsightRecommendation[]> {
+export async function getSchemaInsights(): Promise<
+  SqlApiResponse<InsightRecommendation[]>
+> {
   const request: SqlExecutionRequest = {
     statements: schemaInsightQueries.map(insightQuery => ({
       sql: insightQuery.query,
     })),
     execute: true,
+    max_result_size: LARGE_RESULT_SIZE,
     timeout: LONG_TIMEOUT,
   };
   const result = await executeInternalSql<SchemaInsightResponse>(request);
-  if (result.error) {
-    throw new Error(
-      `Error while retrieving insights information: ${sqlApiErrorMessage(
-        result.error.message,
-      )}`,
-    );
-  }
+
   const results: InsightRecommendation[] = [];
   if (sqlResultsAreEmpty(result)) {
-    // No data.
-    return results;
+    return formatApiResult([], result.error, "retrieving insights information");
   }
   result.execution.txn_results.map(txn_result => {
     // Note: txn_result.statement values begin at 1, not 0.
@@ -210,5 +222,9 @@ export async function getSchemaInsights(): Promise<InsightRecommendation[]> {
       results.push(...insightQuery.toSchemaInsight(txn_result));
     }
   });
-  return results;
+  return formatApiResult(
+    results,
+    result.error,
+    "retrieving insights information",
+  );
 }