diff --git a/CHANGELOG.md b/CHANGELOG.md
index e84d458..ef18179 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,8 +2,11 @@
 
 ## Unreleased
 
-- Bugfix: provider API keys are encrypted in `processDatamap_preProcessFieldArray` instead of only in the post-process hook. On an update, DataHandler captures the `sys_history` diff before the post-process hook runs, so the record history kept the unencrypted value even though the `api_key` column itself was encrypted. Inserts were not affected (#30)
+- Bugfix: the Providers overview and Request Log statistics queries no longer select every column alongside their aggregates, which MySQL rejects outright under `sql_mode=ONLY_FULL_GROUP_BY` (#27)
+- Bugfix: cost and score columns are declared as `decimal` instead of `double(M,D)`. Doctrine drops precision and scale for float types, so the schema comparison reported the same `ALTER TABLE` on every run without the applied statement ever changing the column, leaving "Analyze Database Structure" stuck with a change list that never went away (#27)
 
+- Bugfix: provider API keys are encrypted in `processDatamap_preProcessFieldArray` instead of only in the post-process hook. On an update, DataHandler captures the `sys_history` diff before the post-process hook runs, so the record history kept the unencrypted value even though the `api_key` column itself was encrypted. Inserts were not affected (#30)
+  
   Existing history entries are not rewritten. To drop them for a configuration whose key was changed before this fix:
 
   ```sql
diff --git a/Classes/Domain/Repository/PagePromptFragmentRepository.php b/Classes/Domain/Repository/PagePromptFragmentRepository.php
index 54d5980..7b1f02c 100644
--- a/Classes/Domain/Repository/PagePromptFragmentRepository.php
+++ b/Classes/Domain/Repository/PagePromptFragmentRepository.php
@@ -93,8 +93,14 @@ public function countByDemand(PagePromptFragmentDemand $demand, ?array $accessib
         $qb = $this->getQueryBuilderForDemand($demand, $accessiblePageIds);
         // count() quotes its entire argument as a single identifier, so it
         // can't express "DISTINCT column", addSelectLiteral() with a raw
-        // COUNT(DISTINCT ...) expression is this codebase's own established
-        // way around that (see RequestLogRepository's aggregate queries).
+        // COUNT(DISTINCT ...) expression is the way around that. Safe here
+        // specifically because getQueryBuilderForDemand() never calls
+        // select() itself, so this is the only call that ever populates the
+        // select list; RequestLogRepository's own aggregate queries instead
+        // start from a QueryBuilder that already has an explicit
+        // select('*'), where addSelectLiteral() would append onto that `*`
+        // rather than define the select list from scratch, that's why those
+        // use selectLiteral() (replaces) instead.
         $qb->addSelectLiteral('COUNT(DISTINCT ' . $qb->quoteIdentifier('pages.uid') . ')');
         return (int)$qb->executeQuery()->fetchOne();
     }
diff --git a/Classes/Domain/Repository/RequestLogRepository.php b/Classes/Domain/Repository/RequestLogRepository.php
index 2798614..618a910 100644
--- a/Classes/Domain/Repository/RequestLogRepository.php
+++ b/Classes/Domain/Repository/RequestLogRepository.php
@@ -157,19 +157,7 @@ public function countByDemand(RequestLogDemand $demand): int
 
     public function getStatistics(): array
     {
-        $qb = $this->getQueryBuilder();
-        $result = $qb
-            ->addSelectLiteral(
-                $qb->expr()->count('*', 'total_requests'),
-                'SUM(cost) AS total_cost',
-                'SUM(prompt_tokens) AS total_prompt_tokens',
-                'SUM(completion_tokens) AS total_completion_tokens',
-                'SUM(cached_tokens) AS total_cached_tokens',
-                'SUM(reasoning_tokens) AS total_reasoning_tokens',
-                'SUM(total_tokens) AS total_tokens',
-                'AVG(duration_ms) AS avg_duration_ms',
-                'SUM(success) AS successful_requests',
-            )
+        $result = $this->buildStatisticsQueryBuilder()
             ->executeQuery()
             ->fetchAssociative();
 
@@ -189,11 +177,27 @@ public function getStatistics(): array
         ];
     }
 
+    private function buildStatisticsQueryBuilder(): QueryBuilder
+    {
+        $qb = $this->getQueryBuilder();
+        return $qb->selectLiteral(
+            $qb->expr()->count('*', 'total_requests'),
+            'SUM(cost) AS total_cost',
+            'SUM(prompt_tokens) AS total_prompt_tokens',
+            'SUM(completion_tokens) AS total_completion_tokens',
+            'SUM(cached_tokens) AS total_cached_tokens',
+            'SUM(reasoning_tokens) AS total_reasoning_tokens',
+            'SUM(total_tokens) AS total_tokens',
+            'AVG(duration_ms) AS avg_duration_ms',
+            'SUM(success) AS successful_requests',
+        );
+    }
+
     public function getStatisticsByProvider(): array
     {
         $qb = $this->getQueryBuilder();
         return $qb
-            ->addSelectLiteral(
+            ->selectLiteral(
                 'provider_identifier',
                 $qb->expr()->count('*', 'request_count'),
                 'SUM(cost) AS total_cost',
@@ -211,7 +215,7 @@ public function getStatisticsByExtension(): array
     {
         $qb = $this->getQueryBuilder();
         return $qb
-            ->addSelectLiteral(
+            ->selectLiteral(
                 'extension_key',
                 $qb->expr()->count('*', 'request_count'),
                 'SUM(cost) AS total_cost',
@@ -233,27 +237,7 @@ public function getStatisticsByExtension(): array
      */
     public function getModelPerformanceProfile(string $requestType = ''): array
     {
-        $done = GradeStatus::Done->value;
-        $qb = $this->getQueryBuilder();
-        $qb->addSelectLiteral(
-                'model_used',
-                $qb->expr()->count('*', 'request_count'),
-                'AVG(cost) AS avg_cost',
-                'AVG(duration_ms) AS avg_duration_ms',
-                'SUM(success) AS successful_requests',
-                'AVG(total_tokens) AS avg_tokens',
-                sprintf("SUM(CASE WHEN grade_status = '%s' THEN grade_score ELSE 0 END) AS grade_score_sum", $done),
-                sprintf("SUM(CASE WHEN grade_status = '%s' THEN 1 ELSE 0 END) AS graded_count", $done),
-            );
-        if ($requestType !== '') {
-            $qb->where($qb->expr()->eq('request_type', $qb->createNamedParameter($requestType)));
-            $qb->andWhere($qb->expr()->neq('model_used', $qb->createNamedParameter('')));
-        } else {
-            $qb->where($qb->expr()->neq('model_used', $qb->createNamedParameter('')));
-        }
-        $rows = $qb
-            ->groupBy('model_used')
-            ->orderBy('request_count', 'DESC')
+        $rows = $this->buildModelPerformanceQueryBuilder($requestType)
             ->executeQuery()
             ->fetchAllAssociative();
 
@@ -274,6 +258,31 @@ public function getModelPerformanceProfile(string $requestType = ''): array
         }, $rows);
     }
 
+    private function buildModelPerformanceQueryBuilder(string $requestType): QueryBuilder
+    {
+        $done = GradeStatus::Done->value;
+        $qb = $this->getQueryBuilder();
+        $qb->selectLiteral(
+                'model_used',
+                $qb->expr()->count('*', 'request_count'),
+                'AVG(cost) AS avg_cost',
+                'AVG(duration_ms) AS avg_duration_ms',
+                'SUM(success) AS successful_requests',
+                'AVG(total_tokens) AS avg_tokens',
+                sprintf("SUM(CASE WHEN grade_status = '%s' THEN grade_score ELSE 0 END) AS grade_score_sum", $done),
+                sprintf("SUM(CASE WHEN grade_status = '%s' THEN 1 ELSE 0 END) AS graded_count", $done),
+            );
+        if ($requestType !== '') {
+            $qb->where($qb->expr()->eq('request_type', $qb->createNamedParameter($requestType)));
+            $qb->andWhere($qb->expr()->neq('model_used', $qb->createNamedParameter('')));
+        } else {
+            $qb->where($qb->expr()->neq('model_used', $qb->createNamedParameter('')));
+        }
+        return $qb
+            ->groupBy('model_used')
+            ->orderBy('request_count', 'DESC');
+    }
+
     public function getDistinctProviders(): array
     {
         $qb = $this->getQueryBuilder();
@@ -416,14 +425,7 @@ protected function getQueryBuilderForDemand(RequestLogDemand $demand): QueryBuil
      */
     public function getLastUsedPerConfiguration(): array
     {
-        $qb = $this->getQueryBuilder();
-        $rows = $qb
-            ->addSelectLiteral(
-                'configuration_uid',
-                'MAX(crdate) AS last_used',
-            )
-            ->where($qb->expr()->gt('configuration_uid', $qb->createNamedParameter(0, Connection::PARAM_INT)))
-            ->groupBy('configuration_uid')
+        $rows = $this->buildLastUsedPerConfigurationQueryBuilder()
             ->executeQuery()
             ->fetchAllAssociative();
 
@@ -434,6 +436,18 @@ public function getLastUsedPerConfiguration(): array
         return $result;
     }
 
+    private function buildLastUsedPerConfigurationQueryBuilder(): QueryBuilder
+    {
+        $qb = $this->getQueryBuilder();
+        return $qb
+            ->selectLiteral(
+                'configuration_uid',
+                'MAX(crdate) AS last_used',
+            )
+            ->where($qb->expr()->gt('configuration_uid', $qb->createNamedParameter(0, Connection::PARAM_INT)))
+            ->groupBy('configuration_uid');
+    }
+
     /**
      * Resolve user IDs to usernames from be_users.
      *
diff --git a/Tests/Functional/Domain/Repository/RequestLogRepositoryTest.php b/Tests/Functional/Domain/Repository/RequestLogRepositoryTest.php
index c9a398c..b69639e 100644
--- a/Tests/Functional/Domain/Repository/RequestLogRepositoryTest.php
+++ b/Tests/Functional/Domain/Repository/RequestLogRepositoryTest.php
@@ -74,6 +74,81 @@ public function countByDemandIsUnaffectedByTheUsernameJoin(): void
         self::assertCount(2, $logRepo->findByDemand($demand));
     }
 
+    /**
+     * getQueryBuilder() always starts from an explicit select('*'). Every
+     * aggregate/GROUP BY query built on top of it must REPLACE that select
+     * list (selectLiteral()), not append to it (addSelectLiteral()), or the
+     * `*` leaks every column of the table into the result alongside the
+     * aggregates, which MySQL's ONLY_FULL_GROUP_BY rejects outright
+     * (see https://github.com/b13/aim/issues/27). SQLite tolerates the
+     * broken query and just returns the extra columns, which is exactly
+     * what these tests catch.
+     */
+    #[Test]
+    public function getStatisticsByProviderOnlySelectsTheIntendedColumns(): void
+    {
+        $logRepo = $this->get(RequestLogRepository::class);
+        $logRepo->log(['request_type' => 'TextGenerationRequest', 'provider_identifier' => 'test', 'cost' => 1.0]);
+
+        $rows = $logRepo->getStatisticsByProvider();
+
+        self::assertCount(1, $rows);
+        self::assertSame(
+            ['provider_identifier', 'request_count', 'total_cost', 'total_tokens', 'avg_duration_ms', 'successful_requests'],
+            array_keys($rows[0]),
+        );
+    }
+
+    #[Test]
+    public function getStatisticsByExtensionOnlySelectsTheIntendedColumns(): void
+    {
+        $logRepo = $this->get(RequestLogRepository::class);
+        $logRepo->log(['request_type' => 'TextGenerationRequest', 'provider_identifier' => 'test', 'extension_key' => 'some_ext', 'cost' => 1.0]);
+
+        $rows = $logRepo->getStatisticsByExtension();
+
+        self::assertCount(1, $rows);
+        self::assertSame(
+            ['extension_key', 'request_count', 'total_cost', 'total_tokens', 'avg_duration_ms'],
+            array_keys($rows[0]),
+        );
+    }
+
+    /**
+     * getStatistics(), getModelPerformanceProfile() and
+     * getLastUsedPerConfiguration() all re-key their rows into a fixed
+     * shape before returning, which would silently hide the same `SELECT
+     * *, ...` regression the two tests above catch directly. Asserted here
+     * instead on the built query's own SQL, via the private QueryBuilder
+     * factories those methods were split from for exactly this reason.
+     */
+    #[Test]
+    public function statisticsQueryHasNoStraySelectStar(): void
+    {
+        $logRepo = $this->get(RequestLogRepository::class);
+        $qb = (new \ReflectionMethod($logRepo, 'buildStatisticsQueryBuilder'))->invoke($logRepo);
+
+        self::assertStringNotContainsString('SELECT *,', $qb->getSQL());
+    }
+
+    #[Test]
+    public function modelPerformanceQueryHasNoStraySelectStar(): void
+    {
+        $logRepo = $this->get(RequestLogRepository::class);
+        $qb = (new \ReflectionMethod($logRepo, 'buildModelPerformanceQueryBuilder'))->invoke($logRepo, '');
+
+        self::assertStringNotContainsString('SELECT *,', $qb->getSQL());
+    }
+
+    #[Test]
+    public function lastUsedPerConfigurationQueryHasNoStraySelectStar(): void
+    {
+        $logRepo = $this->get(RequestLogRepository::class);
+        $qb = (new \ReflectionMethod($logRepo, 'buildLastUsedPerConfigurationQueryBuilder'))->invoke($logRepo);
+
+        self::assertStringNotContainsString('SELECT *,', $qb->getSQL());
+    }
+
     #[Test]
     public function modelPerformanceProfileAggregatesGradesOverDoneRowsOnly(): void
     {
diff --git a/ext_tables.sql b/ext_tables.sql
index 70226e6..4736fd2 100644
--- a/ext_tables.sql
+++ b/ext_tables.sql
@@ -27,12 +27,12 @@ CREATE TABLE tx_aim_configuration (
     `default` tinyint(4) unsigned DEFAULT '0' NOT NULL,
     api_key text,
     model varchar(255) DEFAULT '' NOT NULL,
-    total_cost double(10,6) DEFAULT '0.000000' NOT NULL,
+    total_cost decimal(10,6) DEFAULT '0.000000' NOT NULL,
     cost_currency varchar(10) DEFAULT 'USD' NOT NULL,
 
     max_tokens int(11) unsigned DEFAULT '0' NOT NULL,
-    input_token_cost double(10,6) DEFAULT '0.000000' NOT NULL,
-    output_token_cost double(10,6) DEFAULT '0.000000' NOT NULL,
+    input_token_cost decimal(10,6) DEFAULT '0.000000' NOT NULL,
+    output_token_cost decimal(10,6) DEFAULT '0.000000' NOT NULL,
     be_groups varchar(255) DEFAULT '' NOT NULL,
     privacy_level varchar(20) DEFAULT 'standard' NOT NULL,
     rerouting_allowed tinyint(1) unsigned DEFAULT '1' NOT NULL,
@@ -49,7 +49,7 @@ CREATE TABLE tx_aim_usage_budget (
     period_start int(11) unsigned DEFAULT '0' NOT NULL,
     period_type varchar(20) DEFAULT 'monthly' NOT NULL,
     tokens_used int(11) unsigned DEFAULT '0' NOT NULL,
-    cost_used double(10,6) DEFAULT '0.000000' NOT NULL,
+    cost_used decimal(10,6) DEFAULT '0.000000' NOT NULL,
     requests_used int(11) unsigned DEFAULT '0' NOT NULL,
 
     PRIMARY KEY (uid),
@@ -71,7 +71,7 @@ CREATE TABLE tx_aim_request_log (
 	cached_tokens int(11) unsigned DEFAULT '0' NOT NULL,
 	reasoning_tokens int(11) unsigned DEFAULT '0' NOT NULL,
 	total_tokens int(11) unsigned DEFAULT '0' NOT NULL,
-	cost double(10,6) DEFAULT '0.000000' NOT NULL,
+	cost decimal(10,6) DEFAULT '0.000000' NOT NULL,
 	duration_ms int(11) unsigned DEFAULT '0' NOT NULL,
 	system_fingerprint varchar(255) DEFAULT '' NOT NULL,
 	error_message text,
@@ -81,18 +81,18 @@ CREATE TABLE tx_aim_request_log (
 	request_prompt text,
 	request_system_prompt text,
 	response_content text,
-	complexity_score double(5,4) DEFAULT '0.0000' NOT NULL,
+	complexity_score decimal(5,4) DEFAULT '0.0000' NOT NULL,
 	complexity_label varchar(20) DEFAULT '' NOT NULL,
 	complexity_reason text,
 	rerouted tinyint(1) unsigned DEFAULT '0' NOT NULL,
 	reroute_type varchar(20) DEFAULT '' NOT NULL,
 	reroute_reason varchar(255) DEFAULT '' NOT NULL,
 	grade_status varchar(20) DEFAULT 'none' NOT NULL,
-	grade_score double(5,4) DEFAULT '0.0000' NOT NULL,
+	grade_score decimal(5,4) DEFAULT '0.0000' NOT NULL,
 	grade_label varchar(20) DEFAULT '' NOT NULL,
 	grade_reason text,
 	judge_model varchar(255) DEFAULT '' NOT NULL,
-	judge_cost double(10,6) DEFAULT '0.000000' NOT NULL,
+	judge_cost decimal(10,6) DEFAULT '0.000000' NOT NULL,
 	grade_duration_ms int(11) unsigned DEFAULT '0' NOT NULL,
 	grade_error varchar(500) DEFAULT '' NOT NULL,