Issue #2846994 by Gábor Hojtsy, jungle, andypost, daffie, swatichouhan012, xjm, catch, effulgentsia, bzrudi71, mradcliffe, TravisCarden, Mixologic: Increase minimum version requirement for Postgres to 10 and require the pg_trgm extension

core/INSTALL.txt

@@ -56,7 +56,7 @@ Drupal requires:
     compatible drop-in replacement for MySQL.
   - Percona Server 5.7.8 (or greater) (http://www.percona.com/). Percona
     Server is a backwards-compatible replacement for MySQL.
-  - PostgreSQL 9.1.2 (or greater) (http://www.postgresql.org/).
+  - PostgreSQL 10 (or greater) (http://www.postgresql.org/).
   - SQLite 3.26 (or greater) (http://www.sqlite.org/).
 
 For more detailed information about Drupal requirements, including a list of

core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php

@@ -11,6 +11,15 @@ use Drupal\Core\Database\DatabaseNotFoundException;
  */
 class Tasks extends InstallTasks {
 
+  /**
+   * Minimum required PostgreSQL version.
+   *
+   * The contrib extension pg_trgm is supposed to be installed.
+   *
+   * @see https://www.postgresql.org/docs/10/pgtrgm.html
+   */
+  const PGSQL_MINIMUM_VERSION = '10';
+
   /**
    * {@inheritdoc}
    */
@@ -49,7 +58,7 @@ class Tasks extends InstallTasks {
    * {@inheritdoc}
    */
   public function minimumVersion() {
-    return '9.1.2';
+    return static::PGSQL_MINIMUM_VERSION;
   }
 
   /**
@@ -133,10 +142,7 @@ class Tasks extends InstallTasks {
    * Unserializing does not work on Postgresql 9 when bytea_output is 'hex'.
    */
   public function checkBinaryOutput() {
-    // PostgreSQL < 9 doesn't support bytea_output, so verify we are running
-    // at least PostgreSQL 9.
     $database_connection = Database::getConnection();
-    if (version_compare($database_connection->version(), '9') >= 0) {
     if (!$this->checkBinaryOutputSuccess()) {
       // First try to alter the database. If it fails, raise an error telling
       // the user to do it themselves.
@@ -145,7 +151,7 @@ class Tasks extends InstallTasks {
       // code is only called when a connection to the database is already
       // established, thus the database name is guaranteed to be a correct
       // value.
-        $query = "ALTER DATABASE \"" . $connection_options['database'] . "\" SET bytea_output = 'escape';";
+      $query = "ALTER DATABASE \"{$connection_options['database']}\" SET bytea_output = 'escape';";
       try {
         $database_connection->query($query);
       }
@@ -171,7 +177,6 @@ class Tasks extends InstallTasks {
       }
     }
   }
-  }
 
   /**
    * Verify that a binary data roundtrip returns the original string.

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

@@ -380,7 +380,7 @@ EOD;
     }
 
     if (!empty($field['unsigned'])) {
-      // Unsigned data types are not supported in PostgreSQL 9.1. In MySQL,
+      // Unsigned data types are not supported in PostgreSQL 10. In MySQL,
       // they are used to ensure a positive number is inserted and it also
       // doubles the maximum integer size that can be stored in a field.
       // The PostgreSQL schema in Drupal creates a check constraint
@@ -706,7 +706,7 @@ EOD;
    * {@inheritdoc}
    */
   public function indexExists($table, $name) {
-    // Details http://www.postgresql.org/docs/9.1/interactive/view-pg-indexes.html
+    // Details https://www.postgresql.org/docs/10/view-pg-indexes.html
     $index_name = $this->ensureIdentifiersLength($table, $name, 'idx');
     // Remove leading and trailing quotes because the index name is in a WHERE
     // clause and not used as an identifier.