diff --git a/.travis.yml b/.travis.yml
index d76e949..4de4509 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,15 +1,23 @@
 language: php
 
+dist: precise
+
 sudo: false
 
 matrix:
   include:
     - php: 5.3
       env: DB=POSTGRESQL CORE_RELEASE=3.4
+    - php: 5.4
+      env: DB=POSTGRESQL CORE_RELEASE=3.5
+    - php: 5.5
+      env: DB=POSTGRESQL CORE_RELEASE=3.6
     - php: 5.6
       env: DB=POSTGRESQL CORE_RELEASE=3
     - php: 7.0
       env: DB=POSTGRESQL CORE_RELEASE=3
+    - php: 7.1
+      env: DB=POSTGRESQL CORE_RELEASE=3
 
 before_script:
  - composer self-update || true
@@ -19,4 +27,4 @@ before_script:
  - cd ~/builds/ss
 
 script: 
- - vendor/bin/phpunit framework/tests 
+ - vendor/bin/phpunit framework/tests
diff --git a/code/PostgreSQLDatabase.php b/code/PostgreSQLDatabase.php
index e6b247a..b5a2508 100644
--- a/code/PostgreSQLDatabase.php
+++ b/code/PostgreSQLDatabase.php
@@ -2,7 +2,7 @@
 
 /**
  * PostgreSQL connector class.
- * 
+ *
  * @package sapphire
  * @subpackage model
  */
@@ -10,14 +10,14 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * Database schema manager object
-	 * 
+	 *
 	 * @var PostgreSQLSchemaManager
 	 */
 	protected $schemaManager;
 
 	/**
 	 * The currently selected database schema name.
-	 * 
+	 *
 	 * @var string
 	 */
 	protected $schema;
@@ -30,7 +30,7 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * Full text cluster method. (e.g. GIN or GiST)
-	 * 
+	 *
 	 * @return string
 	 */
 	public static function default_fts_cluster_method() {
@@ -39,7 +39,7 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * Full text search method.
-	 * 
+	 *
 	 * @return string
 	 */
 	public static function default_fts_search_method() {
@@ -53,7 +53,7 @@ class PostgreSQLDatabase extends SS_Database {
 	 * Some locked down systems prevent access to the 'postgres' table in
 	 * which case you need to set this to false.
 	 *
-	 * If allow_query_master_postgres is false, and model_schema_as_database is also false, 
+	 * If allow_query_master_postgres is false, and model_schema_as_database is also false,
 	 * then attempts to create or check databases beyond the initial connection will
 	 * result in a runtime error.
 	 */
@@ -67,7 +67,7 @@ class PostgreSQLDatabase extends SS_Database {
 	 * instead of using databases. This may be useful if the database user does not
 	 * have cross-database permissions, and in cases where multiple databases are used
 	 * (such as in running test cases).
-	 * 
+	 *
 	 * If this is true then the database will only be set during the initial connection,
 	 * and attempts to change to this database will use the 'public' schema instead
 	 */
@@ -88,7 +88,7 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * The database name specified at initial connection
-	 * 
+	 *
 	 * @var string
 	 */
 	protected $databaseOriginal = '';
@@ -149,7 +149,7 @@ class PostgreSQLDatabase extends SS_Database {
 			}
 		}
 
-		// Connect to the actual database we're requesting
+			// Connect to the actual database  we 're requesting
 		$this->connectDefault();
 
 		// Set up the schema if required
@@ -175,7 +175,7 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * Sets the system timezone for the database connection
-	 * 
+	 *
 	 * @param string $timezone
 	 */
 	public function selectTimezone($timezone) {
@@ -197,7 +197,7 @@ class PostgreSQLDatabase extends SS_Database {
 
 	/**
 	 * Returns the name of the current schema in use
-	 * 
+	 *
 	 * @return string Name of current schema
 	 */
 	public function currentSchema() {
@@ -207,7 +207,7 @@ class PostgreSQLDatabase extends SS_Database {
 	/**
 	 * Utility method to manually set the schema to an alternative
 	 * Check existance & sets search path to the supplied schema name
-	 * 
+	 *
 	 * @param string $name Name of the schema
 	 * @param boolean $create Flag indicating whether the schema should be created
 	 * if it doesn't exist. If $create is false and the schema doesn't exist
@@ -240,7 +240,7 @@ class PostgreSQLDatabase extends SS_Database {
 	 * the search path is provided as an advanced PostgreSQL feature for raw
 	 * SQL queries. Sapphire cannot search for datamodel tables in alternate
 	 * schemas, so be wary of using alternate schemas within the ORM environment.
-	 * 
+	 *
 	 * @param string $arg1 First schema to use
 	 * @param string $arg2 Second schema to use
 	 * @param string $argN Nth schema to use
@@ -354,12 +354,14 @@ class PostgreSQLDatabase extends SS_Database {
 
 		$fullQuery = "SELECT * FROM (" . implode(" UNION ", $tables) . ") AS q1 $orderBy LIMIT $limit OFFSET $offset";
 
+		// Get the total items in this search
+		$totalItemsQuery = "SELECT COUNT(*) AS totalitems FROM (" . implode(" UNION ", $tables) . ") AS q1";
+		$totalCount = DB::query($totalItemsQuery);
+
 		// Get records
 		$records = $this->preparedQuery($fullQuery, $tableParameters);
-		$totalCount=0;
 		foreach($records as $record){
 			$objects[] = new $record['ClassName']($record);
-			$totalCount++;
 		}
 
 		if(isset($objects)) $results = new ArrayList($objects);
@@ -368,7 +370,7 @@ class PostgreSQLDatabase extends SS_Database {
 		$list->setLimitItems(false);
 		$list->setPageStart($start);
 		$list->setPageLength($pageLength);
-		$list->setTotalItems($totalCount);
+		$list->setTotalItems($totalCount->value());
 		return $list;
 	}
 
@@ -414,6 +416,7 @@ class PostgreSQLDatabase extends SS_Database {
 		$this->query('COMMIT;');
 	}
 
+
 	public function comparisonClause($field, $value, $exact = false, $negate = false, $caseSensitive = null, $parameterised = false) {
 		if($exact && $caseSensitive === null) {
 			$comp = ($negate) ? '!=' : '=';
@@ -422,12 +425,10 @@ class PostgreSQLDatabase extends SS_Database {
 			if($negate) $comp = 'NOT ' . $comp;
 			$field.='::text';
 		}
-
 		if($parameterised) {
 			return sprintf("%s %s ?", $field, $comp);
 		} else {
-			return sprintf("%s %s '%s'", $field, $comp, $value);
-		}
+		return sprintf("%s %s '%s'", $field, $comp, $value);}
 	}
 
 	/**
@@ -536,7 +537,7 @@ class PostgreSQLDatabase extends SS_Database {
 	 * Determines the name of the current database to be reported externally
 	 * by substituting the schema name for the database name.
 	 * Should only be used when model_schema_as_database is true
-	 * 
+	 *
 	 * @param string $schema Name of the schema
 	 * @return string Name of the database to report
 	 */
@@ -550,7 +551,7 @@ class PostgreSQLDatabase extends SS_Database {
 	/**
 	 * Translates a requested database name to a schema name to substitute internally.
 	 * Should only be used when model_schema_as_database is true
-	 * 
+	 *
 	 * @param string $database Name of the database
 	 * @return string Name of the schema to use for this database internally
 	 */
diff --git a/code/PostgreSQLSchemaManager.php b/code/PostgreSQLSchemaManager.php
index b737c30..f52f8a5 100644
--- a/code/PostgreSQLSchemaManager.php
+++ b/code/PostgreSQLSchemaManager.php
@@ -464,7 +464,8 @@ class PostgreSQLSchemaManager extends DBSchemaManager {
 			}
 
 			// SET check constraint (The constraint HAS to be dropped)
-			$existing_constraint=$this->query("SELECT conname FROM pg_constraint WHERE conname='{$tableName}_{$colName}_check';")->value();
+			$constraint_name = "{$tableName}_{$colName}_check";
+			$existing_constraint = $this->constraintExists($constraint_name, false);
 			if(isset($matches[4])) {
 				//Take this new constraint and see what's outstanding from the target table:
 				$constraint_bits=explode('(', $matches[4]);
@@ -488,12 +489,12 @@ class PostgreSQLSchemaManager extends DBSchemaManager {
 
 			//First, delete any existing constraint on this column, even if it's no longer an enum
 			if($existing_constraint) {
-				$alterCol .= ",\nDROP CONSTRAINT \"{$tableName}_{$colName}_check\"";
+				$alterCol .= ",\nDROP CONSTRAINT \"{$constraint_name}\"";
 			}
 
 			//Now create the constraint (if we've asked for one)
 			if(!empty($matches[4])) {
-				$alterCol .= ",\nADD CONSTRAINT \"{$tableName}_{$colName}_check\" $matches[4]";
+				$alterCol .= ",\nADD CONSTRAINT \"{$constraint_name}\" $matches[4]";
 			}
 		}
 
@@ -873,15 +874,25 @@ class PostgreSQLSchemaManager extends DBSchemaManager {
 	 * query all over again.
 	 *
 	 * @param string $constraint
+	 * @param bool $cache Flag whether a cached version should be used. Set to false to cache bust.
+	 * @return false|array Either false, if the constraint doesn't exist, or an array
+	 * with the keys conname and pg_get_constraintdef
 	 */
-	protected function constraintExists($constraint){
-		if(!isset(self::$cached_constraints[$constraint])){
-			$exists = $this->preparedQuery("
+	protected function constraintExists($constraint, $cache = true){
+		if(!$cache || !isset(self::$cached_constraints[$constraint])){
+			$value = $this->preparedQuery("
 				SELECT conname,pg_catalog.pg_get_constraintdef(r.oid, true)
-				FROM pg_catalog.pg_constraint r WHERE r.contype = 'c' AND conname = ? ORDER BY 1;",
-				array($constraint)
+				FROM pg_catalog.pg_constraint r
+				INNER JOIN pg_catalog.pg_namespace n
+				  ON r.connamespace = n.oid
+				WHERE r.contype = 'c' AND conname = ? AND n.nspname = ?
+				ORDER BY 1;",
+				array($constraint, $this->database->currentSchema())
 			)->first();
-			self::$cached_constraints[$constraint]=$exists;
+			if (!$cache) {
+				return $value;
+			}
+			self::$cached_constraints[$constraint] = $value;
 		}
 
 		return self::$cached_constraints[$constraint];
@@ -903,10 +914,13 @@ class PostgreSQLSchemaManager extends DBSchemaManager {
 					WHERE c.relname = ? AND pg_catalog.pg_table_is_visible(c.oid) AND n.nspname = ?
 				);";
 
-		$result = $this->preparedQuery($query, $tableName, $this->database->currentSchema());
+		$result = $this->preparedQuery(
+			$query,
+			array($tableName, $this->database->currentSchema())
+		);
 
 		$table = array();
-		while($row = pg_fetch_assoc($result)) {
+		foreach ($result as $row) {
 			$table[] = array(
 				'Column' => $row['Column'],
 				'DataType' => $row['DataType']
@@ -1388,12 +1402,10 @@ class PostgreSQLSchemaManager extends DBSchemaManager {
 				$this->query("CREATE TABLE \"$partition_name\" (CHECK (" . str_replace('NEW.', '', $partition_value) . ")) INHERITS (\"$tableName\")$tableSpace;");
 			} else {
 				//Drop the constraint, we will recreate in in the next line
-				$existing_constraint = $this->preparedQuery(
-					"SELECT conname FROM pg_constraint WHERE conname = ?;",
-					array("{$partition_name}_pkey")
-				);
+				$constraint_name = "{$partition_name}_pkey";
+				$existing_constraint = $this->constraintExists($constraint_name, false);
 				if($existing_constraint){
-					$this->query("ALTER TABLE \"$partition_name\" DROP CONSTRAINT \"{$partition_name}_pkey\";");
+					$this->query("ALTER TABLE \"$partition_name\" DROP CONSTRAINT \"{$constraint_name}\";");
 				}
 				$this->dropTrigger(strtolower('trigger_' . $tableName . '_insert'), $tableName);
 			}
diff --git a/composer.json b/composer.json
index dedd130..879ed59 100644
--- a/composer.json
+++ b/composer.json
@@ -10,7 +10,7 @@
 		}
 	],
 	"require": {
-		"silverstripe/framework": "^3.2.0"
+		"silverstripe/framework": "^3.2"
 	},
 	"extra": {
 		"branch-alias": {