From aef1dbda85b7037af09beb0d3e0054654718e5c0 Mon Sep 17 00:00:00 2001
From: XingY <xyang@labkey.com>
Date: Tue, 8 Sep 2026 18:59:53 -0700
Subject: [PATCH] GitHub Issue 1534: Cap row counts for React grid pagination

---
 package-lock.json              | 4 ++--
 package.json                   | 2 +-
 src/labkey/query/ExecuteSql.ts | 8 ++++++++
 src/labkey/query/Response.ts   | 2 ++
 src/labkey/query/SelectRows.ts | 8 ++++++++
 5 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 9d52523b..4c37660a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@labkey/api",
-  "version": "1.52.4",
+  "version": "1.52.5-fb-limitMaxCount.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@labkey/api",
-      "version": "1.52.4",
+      "version": "1.52.5-fb-limitMaxCount.1",
       "license": "Apache-2.0",
       "devDependencies": {
         "@babel/core": "8.0.1",
diff --git a/package.json b/package.json
index 991e82b2..df9a1ea1 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@labkey/api",
-  "version": "1.52.4",
+  "version": "1.52.5-fb-limitMaxCount.1",
   "description": "JavaScript client API for LabKey Server",
   "scripts": {
     "build": "npm run build:dist && npm run build:docs",
diff --git a/src/labkey/query/ExecuteSql.ts b/src/labkey/query/ExecuteSql.ts
index 85c8129b..2ffdcb15 100644
--- a/src/labkey/query/ExecuteSql.ts
+++ b/src/labkey/query/ExecuteSql.ts
@@ -39,6 +39,11 @@ export interface ExecuteSqlOptions extends RequestCallbackOptions {
      * If false totalCount will equal number of rows returned (equal to maxRows unless maxRows == 0).
      */
     includeTotalCount?: boolean;
+    /**
+     * Cap the total-count query at this many rows so COUNT(*) is performant. When exceeded the response reports
+     * rowCount clamped to this value and rowCountCapped: true. Omitted or 0 counts exactly (the default).
+     */
+    maxCount?: number;
     /** The maximum number of rows to return from the server (defaults to returning 100,000 rows). */
     maxRows?: number;
     /**
@@ -117,6 +122,9 @@ function buildParams(options: ExecuteSqlOptions): any {
     if (options.includeTotalCount !== undefined) {
         jsonData.includeTotalCount = options.includeTotalCount;
     }
+    if (options.maxCount !== undefined) {
+        jsonData.maxCount = options.maxCount;
+    }
 
     if (options.containerFilter) {
         jsonData.containerFilter = options.containerFilter;
diff --git a/src/labkey/query/Response.ts b/src/labkey/query/Response.ts
index e250a588..33d43339 100644
--- a/src/labkey/query/Response.ts
+++ b/src/labkey/query/Response.ts
@@ -178,6 +178,8 @@ export class Response {
     metaData: ResponseMetadata;
     queryName: string;
     rowCount: number;
+    /** True when rowCount was capped at the request's maxCount rather than counted exactly. Absent unless maxCount was hit. */
+    rowCountCapped?: boolean;
     rows: Row[];
     schemaKey: SchemaKey;
     schemaName: string;
diff --git a/src/labkey/query/SelectRows.ts b/src/labkey/query/SelectRows.ts
index 61533699..82e1ff77 100644
--- a/src/labkey/query/SelectRows.ts
+++ b/src/labkey/query/SelectRows.ts
@@ -63,6 +63,12 @@ export interface SelectRowsOptions extends RequestCallbackOptions {
      * number of rows returned (equal to maxRows unless maxRows == 0).
      */
     includeTotalCount?: boolean;
+    /**
+     * Cap the total-count query at this many rows, so a large grid's COUNT(*) won't do a full scan.
+     * When exceeded the response reports rowCount clamped to this value and rowCountCapped: true. Omitted or 0
+     * counts exactly (the default). Only affects the count; row data is unaffected.
+     */
+    maxCount?: number;
     /**
      * Include the Update (or edit) link column in the set of columns (defaults to false). If included, the column
      * will have the name "~~Update~~". The underlying table/query must support update links or the column
@@ -172,6 +178,8 @@ function buildSelectRowsParams(options: SelectRowsOptions): any {
 
     if (options.includeTotalCount !== undefined) params.includeTotalCount = options.includeTotalCount;
 
+    if (options.maxCount !== undefined) params.maxCount = options.maxCount;
+
     if (options.includeDetailsColumn) params.includeDetailsColumn = options.includeDetailsColumn;
 
     if (options.includeUpdateColumn) params.includeUpdateColumn = options.includeUpdateColumn;