diff --git a/lib/dml/moodle_database.php b/lib/dml/moodle_database.php
index 4828dcf4782..070f0cb9eff 100644
--- a/lib/dml/moodle_database.php
+++ b/lib/dml/moodle_database.php
@@ -924,6 +924,54 @@ abstract class moodle_database {
         }
     }
 
+    /**
+     * Ensures that limit params are numeric and positive integers, to be passed to the database.
+     * We explicitly treat null, '' and -1 as 0 in order to provide compatibility with how limit
+     * values have been passed historically.
+     *
+     * @param int $limitfrom Where to start results from
+     * @param int $limitnum How many results to return
+     * @return array Normalised limit params in array($limitfrom, $limitnum)
+     */
+    protected function normalise_limit_from_num($limitfrom, $limitnum) {
+        global $CFG;
+
+        // We explicilty treat these cases as 0.
+        if ($limitfrom === null || $limitfrom === '' || $limitfrom === -1) {
+            $limitfrom = 0;
+        }
+        if ($limitnum === null || $limitnum === '' || $limitnum === -1) {
+            $limitnum = 0;
+        }
+
+        if ($CFG->debugdeveloper) {
+            if (!is_numeric($limitfrom)) {
+                $strvalue = var_export($limitfrom, true);
+                debugging("Non-numeric limitfrom parameter detected: $strvalue, did you pass the correct arguments?",
+                    DEBUG_DEVELOPER);
+            } else if ($limitfrom < 0) {
+                debugging("Negative limitfrom parameter detected: $limitfrom, did you pass the correct arguments?",
+                    DEBUG_DEVELOPER);
+            }
+
+            if (!is_numeric($limitnum)) {
+                $strvalue = var_export($limitnum, true);
+                debugging("Non-numeric limitnum parameter detected: $strvalue, did you pass the correct arguments?",
+                    DEBUG_DEVELOPER);
+            } else if ($limitnum < 0) {
+                debugging("Negative limitnum parameter detected: $limitnum, did you pass the correct arguments?",
+                    DEBUG_DEVELOPER);
+            }
+        }
+
+        $limitfrom = (int)$limitfrom;
+        $limitnum  = (int)$limitnum;
+        $limitfrom = max(0, $limitfrom);
+        $limitnum  = max(0, $limitnum);
+
+        return array($limitfrom, $limitnum);
+    }
+
     /**
      * Return tables in database WITHOUT current prefix.
      * @param bool $usecache if true, returns list of cached tables.
diff --git a/lib/dml/mssql_native_moodle_database.php b/lib/dml/mssql_native_moodle_database.php
index 70bd6f32bec..0a324b1c176 100644
--- a/lib/dml/mssql_native_moodle_database.php
+++ b/lib/dml/mssql_native_moodle_database.php
@@ -693,10 +693,9 @@ class mssql_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_recordset_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
+
         if ($limitfrom or $limitnum) {
             if ($limitnum >= 1) { // Only apply TOP clause if we have any limitnum (limitfrom offset is handled later)
                 $fetch = $limitfrom + $limitnum;
diff --git a/lib/dml/mysqli_native_moodle_database.php b/lib/dml/mysqli_native_moodle_database.php
index 34320d95432..3cb62a33ea5 100644
--- a/lib/dml/mysqli_native_moodle_database.php
+++ b/lib/dml/mysqli_native_moodle_database.php
@@ -912,10 +912,8 @@ class mysqli_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_recordset_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
 
         if ($limitfrom or $limitnum) {
             if ($limitnum < 1) {
@@ -976,10 +974,8 @@ class mysqli_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_records_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
 
         if ($limitfrom or $limitnum) {
             if ($limitnum < 1) {
diff --git a/lib/dml/oci_native_moodle_database.php b/lib/dml/oci_native_moodle_database.php
index 0c6f700d5b6..00f79d6576c 100644
--- a/lib/dml/oci_native_moodle_database.php
+++ b/lib/dml/oci_native_moodle_database.php
@@ -712,11 +712,7 @@ class oci_native_moodle_database extends moodle_database {
      */
     private function get_limit_sql($sql, array $params = null, $limitfrom=0, $limitnum=0) {
 
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
-
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
         // TODO: Add the /*+ FIRST_ROWS */ hint if there isn't another hint
 
         if ($limitfrom and $limitnum) {
diff --git a/lib/dml/pgsql_native_moodle_database.php b/lib/dml/pgsql_native_moodle_database.php
index 5c369a73e24..2ee1635843c 100644
--- a/lib/dml/pgsql_native_moodle_database.php
+++ b/lib/dml/pgsql_native_moodle_database.php
@@ -681,10 +681,9 @@ class pgsql_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_recordset_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
+
         if ($limitfrom or $limitnum) {
             if ($limitnum < 1) {
                 $limitnum = "ALL";
@@ -724,10 +723,9 @@ class pgsql_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_records_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum  = (int)$limitnum;
-        $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
-        $limitnum  = ($limitnum < 0)  ? 0 : $limitnum;
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
+
         if ($limitfrom or $limitnum) {
             if ($limitnum < 1) {
                 $limitnum = "ALL";
diff --git a/lib/dml/sqlsrv_native_moodle_database.php b/lib/dml/sqlsrv_native_moodle_database.php
index 6f1252486c3..f6cab36050f 100644
--- a/lib/dml/sqlsrv_native_moodle_database.php
+++ b/lib/dml/sqlsrv_native_moodle_database.php
@@ -762,10 +762,8 @@ class sqlsrv_native_moodle_database extends moodle_database {
      * @throws dml_exception A DML specific exception is thrown for any errors.
      */
     public function get_recordset_sql($sql, array $params = null, $limitfrom = 0, $limitnum = 0) {
-        $limitfrom = (int)$limitfrom;
-        $limitnum = (int)$limitnum;
-        $limitfrom = max(0, $limitfrom);
-        $limitnum = max(0, $limitnum);
+
+        list($limitfrom, $limitnum) = $this->normalise_limit_from_num($limitfrom, $limitnum);
 
         if ($limitfrom or $limitnum) {
             if ($limitnum >= 1) { // Only apply TOP clause if we have any limitnum (limitfrom offset is handled later)
diff --git a/lib/dml/tests/dml_test.php b/lib/dml/tests/dml_test.php
index ceed3dbc626..869d6baea57 100644
--- a/lib/dml/tests/dml_test.php
+++ b/lib/dml/tests/dml_test.php
@@ -4997,6 +4997,74 @@ class core_dml_testcase extends database_driver_testcase {
         $this->assertEquals(2, reset($records)->count);
         $this->assertEquals(2, end($records)->count);
     }
+
+    /**
+     * Test debugging messages about invalid limit number values.
+     */
+    public function test_invalid_limits_debugging() {
+        $DB = $this->tdb;
+        $dbman = $DB->get_manager();
+
+        // Setup test data.
+        $table = $this->get_test_table();
+        $tablename = $table->getName();
+        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
+        $table->add_field('course', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
+        $table->add_key('primary', XMLDB_KEY_PRIMARY, array('id'));
+        $dbman->create_table($table);
+        $DB->insert_record($tablename, array('course' => '1'));
+
+        // Verify that get_records_sql throws debug notices with invalid limit params.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 'invalid');
+        $this->assertDebuggingCalled("Non-numeric limitfrom parameter detected: 'invalid', did you pass the correct arguments?");
+
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, 'invalid');
+        $this->assertDebuggingCalled("Non-numeric limitnum parameter detected: 'invalid', did you pass the correct arguments?");
+
+        // Verify that get_recordset_sql throws debug notices with invalid limit params.
+        $rs = $DB->get_recordset_sql("SELECT * FROM {{$tablename}}", null, 'invalid');
+        $this->assertDebuggingCalled("Non-numeric limitfrom parameter detected: 'invalid', did you pass the correct arguments?");
+        $rs->close();
+
+        $rs = $DB->get_recordset_sql("SELECT * FROM {{$tablename}}", null, 1, 'invalid');
+        $this->assertDebuggingCalled("Non-numeric limitnum parameter detected: 'invalid', did you pass the correct arguments?");
+        $rs->close();
+
+        // Verify that some edge cases do no create debugging messages.
+        // String form of integer values.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, '1');
+        $this->assertDebuggingNotCalled();
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, '2');
+        $this->assertDebuggingNotCalled();
+        // Empty strings.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, '');
+        $this->assertDebuggingNotCalled();
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, '');
+        $this->assertDebuggingNotCalled();
+        // Null values.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, null);
+        $this->assertDebuggingNotCalled();
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, null);
+        $this->assertDebuggingNotCalled();
+
+        // Verify that empty arrays DO create debugging mesages.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, array());
+        $this->assertDebuggingCalled("Non-numeric limitfrom parameter detected: array (\n), did you pass the correct arguments?");
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, array());
+        $this->assertDebuggingCalled("Non-numeric limitnum parameter detected: array (\n), did you pass the correct arguments?");
+
+        // Verify Negative number handling:
+        // -1 is explicitly treated as 0 for historical reasons.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, -1);
+        $this->assertDebuggingNotCalled();
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, -1);
+        $this->assertDebuggingNotCalled();
+        // Any other negative values should throw debugging messages.
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, -2);
+        $this->assertDebuggingCalled("Negative limitfrom parameter detected: -2, did you pass the correct arguments?");
+        $DB->get_records_sql("SELECT * FROM {{$tablename}}", null, 1, -2);
+        $this->assertDebuggingCalled("Negative limitnum parameter detected: -2, did you pass the correct arguments?");
+    }
 }
 
 /**