diff --git a/reportbuilder/classes/local/filters/base.php b/reportbuilder/classes/local/filters/base.php
index 5316a656913..86dac541fa2 100644
--- a/reportbuilder/classes/local/filters/base.php
+++ b/reportbuilder/classes/local/filters/base.php
@@ -102,6 +102,9 @@ abstract class base {
     /**
      * Returns the filter clauses to be used with SQL where
      *
+     * Ideally the field SQL should be included only once in the returned expression, however if that is unavoidable then
+     * use the {@see filter::get_field_sql_and_params} helper to ensure uniqueness of any parameters included within
+     *
      * @param array $values
      * @return array [$sql, [...$params]]
      */
diff --git a/reportbuilder/classes/local/filters/category.php b/reportbuilder/classes/local/filters/category.php
index 1cb4552f024..578cfc4ca5e 100644
--- a/reportbuilder/classes/local/filters/category.php
+++ b/reportbuilder/classes/local/filters/category.php
@@ -61,8 +61,7 @@ class category extends base {
     public function get_sql_filter(array $values): array {
         global $DB;
 
-        $fieldsql = $this->filter->get_field_sql();
-        $params = $this->filter->get_field_params();
+        [$fieldsql, $params] = $this->filter->get_field_sql_and_params();
 
         $category = (int) ($values["{$this->name}_value"] ?? 0);
         $subcategories = !empty($values["{$this->name}_subcategories"]);
@@ -79,6 +78,11 @@ class category extends base {
 
         // Sub-category matching on path of selected category.
         if ($subcategories) {
+
+            // We need to re-use the original filter SQL here, while ensuring parameter uniqueness is preserved.
+            [$fieldsql, $params1] = $this->filter->get_field_sql_and_params(1);
+            $params = array_merge($params, $params1);
+
             $paramcategorypath = database::generate_param_name();
             $params[$paramcategorypath] = "%/{$category}/%";
             $sql .= " OR {$fieldsql} IN (
diff --git a/reportbuilder/classes/local/filters/date.php b/reportbuilder/classes/local/filters/date.php
index 59a32bdedac..5c9a8b6a38d 100644
--- a/reportbuilder/classes/local/filters/date.php
+++ b/reportbuilder/classes/local/filters/date.php
@@ -175,30 +175,31 @@ class date extends base {
 
         switch ($operator) {
             case self::DATE_NOT_EMPTY:
-                $sql = "{$fieldsql} IS NOT NULL AND {$fieldsql} <> 0";
+                $sql = "COALESCE({$fieldsql}, 0) <> 0";
                 break;
             case self::DATE_EMPTY:
-                $sql = "{$fieldsql} IS NULL OR {$fieldsql} = 0";
+                $sql = "COALESCE({$fieldsql}, 0) = 0";
                 break;
             case self::DATE_RANGE:
-                $clauses = [];
+                $sql = '';
 
                 $datefrom = (int)($values["{$this->name}_from"] ?? 0);
-                if ($datefrom > 0) {
-                    $paramdatefrom = database::generate_param_name();
-                    $clauses[] = "{$fieldsql} >= :{$paramdatefrom}";
-                    $params[$paramdatefrom] = $datefrom;
-                }
-
                 $dateto = (int)($values["{$this->name}_to"] ?? 0);
-                if ($dateto > 0) {
-                    $paramdateto = database::generate_param_name();
-                    $clauses[] = "{$fieldsql} < :{$paramdateto}";
+
+                [$paramdatefrom, $paramdateto] = database::generate_param_names(2);
+
+                if ($datefrom > 0 && $dateto > 0) {
+                    $sql = "{$fieldsql} BETWEEN :{$paramdatefrom} AND :{$paramdateto}";
+                    $params[$paramdatefrom] = $datefrom;
+                    $params[$paramdateto] = $dateto;
+                } else if ($datefrom > 0) {
+                    $sql = "{$fieldsql} >= :{$paramdatefrom}";
+                    $params[$paramdatefrom] = $datefrom;
+                } else if ($dateto > 0) {
+                    $sql = "{$fieldsql} < :{$paramdateto}";
                     $params[$paramdateto] = $dateto;
                 }
 
-                $sql = implode(' AND ', $clauses);
-
                 break;
             case self::DATE_BEFORE:
                 $param = database::generate_param_name();
@@ -219,7 +220,7 @@ class date extends base {
 
                 // Generate parameters and SQL clause for the relative date comparison.
                 [$paramdatefrom, $paramdateto] = database::generate_param_names(2);
-                $sql = "{$fieldsql} >= :{$paramdatefrom} AND {$fieldsql} <= :{$paramdateto}";
+                $sql = "{$fieldsql} BETWEEN :{$paramdatefrom} AND :{$paramdateto}";
 
                 [
                     $params[$paramdatefrom],
diff --git a/reportbuilder/classes/local/filters/number.php b/reportbuilder/classes/local/filters/number.php
index 034c2792c8c..f884b659915 100644
--- a/reportbuilder/classes/local/filters/number.php
+++ b/reportbuilder/classes/local/filters/number.php
@@ -132,10 +132,10 @@ class number extends base {
             case self::ANY_VALUE:
                 return ['', []];
             case self::IS_NOT_EMPTY:
-                $res = "{$fieldsql} IS NOT NULL AND {$fieldsql} <> 0";
+                $res = "COALESCE({$fieldsql}, 0) <> 0";
                 break;
             case self::IS_EMPTY:
-                $res = "{$fieldsql} IS NULL OR {$fieldsql} = 0";
+                $res = "COALESCE({$fieldsql}, 0) = 0";
                 break;
             case self::LESS_THAN:
                 $res = "{$fieldsql} < :{$param}";
@@ -158,7 +158,7 @@ class number extends base {
                 $params[$param] = $value1;
                 break;
             case self::RANGE:
-                $res = "({$fieldsql} >= :{$param} AND {$fieldsql} <= :{$param2})";
+                $res = "{$fieldsql} BETWEEN :{$param} AND :{$param2}";
                 $params[$param] = $value1;
                 $params[$param2] = $value2;
                 break;
diff --git a/reportbuilder/classes/local/helpers/database.php b/reportbuilder/classes/local/helpers/database.php
index de250176270..a19694c12b7 100644
--- a/reportbuilder/classes/local/helpers/database.php
+++ b/reportbuilder/classes/local/helpers/database.php
@@ -101,6 +101,29 @@ class database {
         return true;
     }
 
+    /**
+     * Replace parameter names within given SQL expression, allowing caller to specify callback to handle their replacement
+     * primarily to ensure uniqueness when the expression is to be used as part of a larger query
+     *
+     * @param string $sql
+     * @param array $params
+     * @param callable $callback Method that takes a single string parameter, and returns another string
+     * @return string
+     */
+    public static function sql_replace_parameter_names(string $sql, array $params, callable $callback): string {
+        foreach ($params as $param) {
+
+            // Pattern to look for param within the SQL.
+            $pattern = '/:(?<param>' . preg_quote($param) . ')\b/';
+
+            $sql = preg_replace_callback($pattern, function(array $matches) use ($callback): string {
+                return ':' . $callback($matches['param']);
+            }, $sql);
+        }
+
+        return $sql;
+    }
+
     /**
      * Generate SQL expression for sorting group concatenated fields
      *
diff --git a/reportbuilder/classes/local/report/column.php b/reportbuilder/classes/local/report/column.php
index 3db57db8ba5..05c64ef49f1 100644
--- a/reportbuilder/classes/local/report/column.php
+++ b/reportbuilder/classes/local/report/column.php
@@ -367,12 +367,12 @@ final class column {
         $fields = [];
 
         foreach ($this->fields as $alias => $sql) {
-            // Ensure params within SQL are prefixed with column index.
-            foreach ($this->params as $name => $value) {
-                $sql = preg_replace_callback('/:(?<param>' . preg_quote($name, '\b/') . ')/', function(array $matches): string {
-                    return ':' . $this->unique_param_name($matches['param']);
-                }, $sql);
-            }
+
+            // Ensure parameter names within SQL are prefixed with column index.
+            $params = array_keys($this->params);
+            $sql = database::sql_replace_parameter_names($sql, $params, function(string $param): string {
+                return $this->unique_param_name($param);
+            });
 
             $fields[$alias] = [
                 'sql' => $sql,
diff --git a/reportbuilder/classes/local/report/filter.php b/reportbuilder/classes/local/report/filter.php
index d45466b70d3..dbd731d778e 100644
--- a/reportbuilder/classes/local/report/filter.php
+++ b/reportbuilder/classes/local/report/filter.php
@@ -21,6 +21,7 @@ namespace core_reportbuilder\local\report;
 use lang_string;
 use moodle_exception;
 use core_reportbuilder\local\filters\base;
+use core_reportbuilder\local\helpers\database;
 use core_reportbuilder\local\models\filter as filter_model;
 
 /**
@@ -212,6 +213,38 @@ final class filter {
         return $this->fieldparams;
     }
 
+    /**
+     * Retrieve SQL expression and parameters for the field
+     *
+     * @param int $index
+     * @return array [$sql, [...$params]]
+     */
+    public function get_field_sql_and_params(int $index = 0): array {
+        $fieldsql = $this->get_field_sql();
+        $fieldparams = $this->get_field_params();
+
+        // Shortcut if there aren't any parameters.
+        if (empty($fieldparams)) {
+            return [$fieldsql, $fieldparams];
+        }
+
+        // Simple callback for replacement of parameter names within filter SQL.
+        $transform = function(string $param) use ($index): string {
+            return "{$param}_{$index}";
+        };
+
+        $paramnames = array_keys($fieldparams);
+        $sql = database::sql_replace_parameter_names($fieldsql, $paramnames, $transform);
+
+        $params = [];
+        foreach ($paramnames as $paramname) {
+            $paramnametransform = $transform($paramname);
+            $params[$paramnametransform] = $fieldparams[$paramname];
+        }
+
+        return [$sql, $params];
+    }
+
     /**
      * Set the SQL expression for the field that is being filtered. It will be passed to the filter class
      *
diff --git a/reportbuilder/tests/local/filters/category_test.php b/reportbuilder/tests/local/filters/category_test.php
index 819d158a03f..06e60ad8b09 100644
--- a/reportbuilder/tests/local/filters/category_test.php
+++ b/reportbuilder/tests/local/filters/category_test.php
@@ -20,6 +20,7 @@ namespace core_reportbuilder\local\filters;
 
 use advanced_testcase;
 use lang_string;
+use core_reportbuilder\local\helpers\database;
 use core_reportbuilder\local\report\filter;
 
 /**
@@ -88,4 +89,37 @@ class category_test extends advanced_testcase {
         $categories = $DB->get_fieldset_select('course_categories', 'name', $select, $params);
         $this->assertEqualsCanonicalizing($expectedcategories, $categories);
     }
+
+    /**
+     * Test getting filter SQL with parameters
+     */
+    public function test_get_sql_filter_parameters(): void {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        $category1 = $this->getDataGenerator()->create_category(['name' => 'One']);
+        $category2 = $this->getDataGenerator()->create_category(['name' => 'Two', 'parent' => $category1->id]);
+        $category3 = $this->getDataGenerator()->create_category(['name' => 'Three']);
+
+        // Rather convoluted filter SQL, but enough to demonstrate usage of a parameter that gets used twice in the query.
+        $paramzero = database::generate_param_name();
+        $filter = new filter(
+            category::class,
+            'test',
+            new lang_string('yes'),
+            'testentity',
+            "id + :{$paramzero}",
+            [$paramzero => 0]
+        );
+
+        // When including sub-categories, the filter SQL is included twice (for the category itself, plus to find descendents).
+        [$select, $params] = category::create($filter)->get_sql_filter([
+            $filter->get_unique_identifier() . '_value' => $category1->id,
+            $filter->get_unique_identifier() . '_subcategories' => true,
+        ]);
+
+        $categories = $DB->get_fieldset_select('course_categories', 'id', $select, $params);
+        $this->assertEqualsCanonicalizing([$category1->id, $category2->id], $categories);
+    }
 }
diff --git a/reportbuilder/tests/local/helpers/database_test.php b/reportbuilder/tests/local/helpers/database_test.php
index 5dc496b5d51..22df8614a49 100644
--- a/reportbuilder/tests/local/helpers/database_test.php
+++ b/reportbuilder/tests/local/helpers/database_test.php
@@ -139,4 +139,31 @@ class database_test extends advanced_testcase {
         $record = $DB->get_record_sql($sql, $params);
         $this->assertEquals($admin->id, $record->{$userfieldalias});
     }
+
+    /**
+     * Test replacement of parameter names within SQL statements
+     */
+    public function test_sql_replace_parameter_names(): void {
+        global $DB;
+
+        // Predefine parameter names, to ensure they don't overwrite each other.
+        [$param0, $param1, $param10] = ['rbparam0', 'rbparam1', 'rbparam10'];
+
+        $sql = "SELECT :{$param0} AS field0, :{$param1} AS field1, :{$param10} AS field10" . $DB->sql_null_from_clause();
+        $sql = database::sql_replace_parameter_names($sql, [$param0, $param1, $param10], static function(string $param): string {
+            return "prefix_{$param}";
+        });
+
+        $record = $DB->get_record_sql($sql, [
+            "prefix_{$param0}" => 'Zero',
+            "prefix_{$param1}" => 'One',
+            "prefix_{$param10}" => 'Ten',
+        ]);
+
+        $this->assertEquals((object) [
+            'field0' => 'Zero',
+            'field1' => 'One',
+            'field10' => 'Ten',
+        ], $record);
+    }
 }
diff --git a/reportbuilder/tests/local/report/column_test.php b/reportbuilder/tests/local/report/column_test.php
index c9483005f3a..3b29dba4dc1 100644
--- a/reportbuilder/tests/local/report/column_test.php
+++ b/reportbuilder/tests/local/report/column_test.php
@@ -173,19 +173,31 @@ class column_test extends advanced_testcase {
      * Test adding params to field, and retrieving them
      */
     public function test_add_field_with_params(): void {
-        $param = database::generate_param_name();
+        [$param0, $param1] = database::generate_param_names(2);
 
         $column = $this->create_column('test')
             ->set_index(1)
-            ->add_field(":{$param}", 'foo', [$param => 'bar']);
+            ->add_field(":{$param0}", 'foo', [$param0 => 'foo'])
+            ->add_field(":{$param1}", 'bar', [$param1 => 'bar']);
 
         // Select will look like the following: "p<index>_rbparam<counter>", where index is the column index and counter is
         // a static value of the report helper class.
-        $select = $column->get_fields();
-        preg_match('/:(?<paramname>p1_rbparam[\d]+) AS c1_foo/', $select[0], $matches);
+        $fields = $column->get_fields();
+        $this->assertCount(2, $fields);
 
+        preg_match('/:(?<paramname>p1_rbparam[\d]+) AS c1_foo/', $fields[0], $matches);
         $this->assertArrayHasKey('paramname', $matches);
-        $this->assertEquals([$matches['paramname'] => 'bar'], $column->get_params());
+        $fieldparam0 = $matches['paramname'];
+
+        preg_match('/:(?<paramname>p1_rbparam[\d]+) AS c1_bar/', $fields[1], $matches);
+        $this->assertArrayHasKey('paramname', $matches);
+        $fieldparam1 = $matches['paramname'];
+
+        // Ensure column parameters have been renamed appropriately.
+        $this->assertEquals([
+            $fieldparam0 => 'foo',
+            $fieldparam1 => 'bar',
+        ], $column->get_params());
     }
 
     /**
diff --git a/reportbuilder/tests/local/report/filter_test.php b/reportbuilder/tests/local/report/filter_test.php
index ed180b5d5a6..299d599a11a 100644
--- a/reportbuilder/tests/local/report/filter_test.php
+++ b/reportbuilder/tests/local/report/filter_test.php
@@ -108,6 +108,18 @@ class filter_test extends advanced_testcase {
         $this->assertEquals(['foo' => 'bar'], $filter->get_field_params());
     }
 
+    /**
+     * Test getting field SQL and params, while providing index for uniqueness
+     */
+    public function test_get_field_sql_and_params(): void {
+        $filter = $this->create_filter('username', 'u.username = :username AND u.idnumber = :idnumber',
+            ['username' => 'test', 'idnumber' => 'bar']);
+
+        [$sql, $params] = $filter->get_field_sql_and_params(1);
+        $this->assertEquals('u.username = :username_1 AND u.idnumber = :idnumber_1', $sql);
+        $this->assertEquals(['username_1' => 'test', 'idnumber_1' => 'bar'], $params);
+    }
+
     /**
      * Test adding single join
      */
diff --git a/reportbuilder/upgrade.txt b/reportbuilder/upgrade.txt
index 8414a8df627..6cd884281f6 100644
--- a/reportbuilder/upgrade.txt
+++ b/reportbuilder/upgrade.txt
@@ -7,6 +7,10 @@ Information provided here is intended especially for developers.
 * Column callbacks are now passed a fourth argument to indicate the aggregation type currently being applied, which allows
   for columns to define how the aggregated data is displayed
 * New methods `[add|get]_attributes` added to report base class, for including custom attributes in report container HTML
+* New database helper method `sql_replace_parameter_names` to help ensure uniqueness of parameters within an expression (where
+  that expression can be used multiple times as part of a larger query)
+* The local report filter class has a new `get_field_sql_and_params` method which should be used by filter types that re-use
+  the filter field SQL within their generated expression, to ensure SQL containing parameters works correctly
 * The following attributes can be added to custom reports in order to control card view display (via the `add_attributes` method):
   - `data-force-card` to force cards view
   - `data-force-table` to force table view