From 13b22525b2c2a85958027a59a979c7b3ecf3555e Mon Sep 17 00:00:00 2001
From: Thomas Hulst <thomas.hulst@farminform.nl>
Date: Thu, 16 May 2024 13:55:08 +0200
Subject: [PATCH 1/4] fix mssql sql_runif() to return random number for each
 row in result set

---
 R/backend-mssql.R | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/R/backend-mssql.R b/R/backend-mssql.R
index 1850e6d89..b64493ed4 100644
--- a/R/backend-mssql.R
+++ b/R/backend-mssql.R
@@ -294,7 +294,8 @@ simulate_mssql <- function(version = "15.0") {
       is.na         = mssql_is_null,
 
       runif = function(n = n(), min = 0, max = 1) {
-        sql_runif(RAND(), n = {{ n }}, min = min, max = max)
+        # https://stackoverflow.com/a/9039661
+        sql_runif(RAND(CHECKSUM(NEWID())), n = {{ n }}, min = min, max = max)
       },
 
       # string functions ------------------------------------------------

From 36e7498731ff8ffe7bc119fb22a167b549d9c281 Mon Sep 17 00:00:00 2001
From: Thomas Hulst <thomas.hulst@farminform.nl>
Date: Thu, 16 May 2024 14:31:11 +0200
Subject: [PATCH 2/4] CHECKSUM and NEWID to globalVariables()

---
 R/backend-mssql.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/backend-mssql.R b/R/backend-mssql.R
index b64493ed4..1415151f7 100644
--- a/R/backend-mssql.R
+++ b/R/backend-mssql.R
@@ -660,4 +660,4 @@ bit_to_boolean <- function(x_expr) {
   }
 }
 
-utils::globalVariables(c("BIT", "CAST", "%AS%", "%is%", "convert", "DATE", "DATEADD", "DATEFROMPARTS", "DATEDIFF", "DATENAME", "DATEPART", "IIF", "NOT", "SUBSTRING", "LTRIM", "RTRIM", "CHARINDEX", "SYSDATETIME", "SECOND", "MINUTE", "HOUR", "DAY", "DAYOFWEEK", "DAYOFYEAR", "MONTH", "QUARTER", "YEAR", "BIGINT", "INT", "%AND%", "%BETWEEN%"))
+utils::globalVariables(c("BIT", "CAST", "%AS%", "%is%", "convert", "DATE", "DATEADD", "DATEFROMPARTS", "DATEDIFF", "DATENAME", "DATEPART", "IIF", "NOT", "SUBSTRING", "LTRIM", "RTRIM", "CHARINDEX", "SYSDATETIME", "SECOND", "MINUTE", "HOUR", "DAY", "DAYOFWEEK", "DAYOFYEAR", "MONTH", "QUARTER", "YEAR", "BIGINT", "INT", "%AND%", "%BETWEEN%", "CHECKSUM", "NEWID"))

From 9b93c4cf003b5f55dc2ee1393c94f17bb401484e Mon Sep 17 00:00:00 2001
From: Thomas Hulst <thomas.hulst@farminform.nl>
Date: Thu, 16 May 2024 14:36:24 +0200
Subject: [PATCH 3/4] update snapshot

---
 tests/testthat/_snaps/backend-mssql.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/testthat/_snaps/backend-mssql.md b/tests/testthat/_snaps/backend-mssql.md
index f17f8175c..0fd81d2a8 100644
--- a/tests/testthat/_snaps/backend-mssql.md
+++ b/tests/testthat/_snaps/backend-mssql.md
@@ -231,7 +231,7 @@
       <SQL>
       SELECT `x`
       FROM (
-        SELECT `df`.*, ROW_NUMBER() OVER (ORDER BY RAND()) AS `col01`
+        SELECT `df`.*, ROW_NUMBER() OVER (ORDER BY RAND(CHECKSUM(NEWID()))) AS `col01`
         FROM `df`
       ) AS `q01`
       WHERE (`col01` <= 1)

From 4900c82ed941c8f08228ba1ebfa37b5f7ad7aa64 Mon Sep 17 00:00:00 2001
From: Hadley Wickham <h.wickham@gmail.com>
Date: Wed, 26 Nov 2025 14:07:35 +0200
Subject: [PATCH 4/4] Add news bullet

---
 NEWS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/NEWS.md b/NEWS.md
index b9e722733..85f0c3146 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,6 @@
 # dbplyr (development version)
 
+* SQL server: `slice_sample()` returns different results each run (@thomashulst, #1503)
 * Fixed overwrite flag in `copy_to()` to work when source is in the same DB as destination (@liudvikasakelis, #1535)
 * Snowflake correctly translates `$` to `:` (@jsowder, #1608)
 * `dbplyr_uncount()` now works with Redshift (@owenjonesuob, #1601).