Issue #3159073 by amateescu, andypost, daffie: Use the new UPSERT capability from SQLite 3.24

core/lib/Drupal/Core/Database/Driver/pgsql/Upsert.php

@@ -100,8 +100,8 @@ public function __toString() {
 
     // Default fields are always placed first for consistency.
     $insert_fields = array_merge($this->defaultFields, $this->insertFields);
-    $insert_fields = array_map(function ($f) {
-      return $this->connection->escapeField($f);
+    $insert_fields = array_map(function ($field) {
+      return $this->connection->escapeField($field);
     }, $insert_fields);
 
     $query = $comments . 'INSERT INTO {' . $this->table . '} (' . implode(', ', $insert_fields) . ') VALUES ';
@@ -114,6 +114,8 @@ public function __toString() {
 
     $update = [];
     foreach ($insert_fields as $field) {
+      // The "excluded." prefix causes the field to refer to the value for field
+      // that would have been inserted had there been no conflict.
       $update[] = "$field = EXCLUDED.$field";
     }
 

core/lib/Drupal/Core/Database/Driver/sqlite/Upsert.php

@@ -6,6 +6,8 @@
 
 /**
  * SQLite implementation of \Drupal\Core\Database\Query\Upsert.
+ *
+ * @see https://www.sqlite.org/lang_UPSERT.html
  */
 class Upsert extends QueryUpsert {
 
@@ -22,11 +24,23 @@ public function __toString() {
       return $this->connection->escapeField($field);
     }, $insert_fields);
 
-    $query = $comments . 'INSERT OR REPLACE INTO {' . $this->table . '} (' . implode(', ', $insert_fields) . ') VALUES ';
+    $query = $comments . 'INSERT INTO {' . $this->table . '} (' . implode(', ', $insert_fields) . ') VALUES ';
 
     $values = $this->getInsertPlaceholderFragment($this->insertValues, $this->defaultFields);
     $query .= implode(', ', $values);
 
+    // Updating the unique / primary key is not necessary.
+    unset($insert_fields[$this->key]);
+
+    $update = [];
+    foreach ($insert_fields as $field) {
+      // The "excluded." prefix causes the field to refer to the value for field
+      // that would have been inserted had there been no conflict.
+      $update[] = "$field = EXCLUDED.$field";
+    }
+
+    $query .= ' ON CONFLICT (' . $this->connection->escapeField($this->key) . ') DO UPDATE SET ' . implode(', ', $update);
+
     return $query;
   }