fix it using lower, can use a function based index

lib/private/DB/AdapterOCI8.php

@@ -40,7 +40,7 @@ public function lastInsertId($table) {
 
 	public function fixupStatement($statement) {
 		$statement = \preg_replace('( LIKE \?)', '$0 ESCAPE \'\\\'', $statement);
-		$statement = \preg_replace('/`(\w+)` ILIKE \?/', 'REGEXP_LIKE(`$1`, \'^\' || REPLACE(?, \'%\', \'.*\') || \'$\', \'i\')', $statement);
+		$statement = \preg_replace('/`(\w+)` ILIKE \?/', "LOWER(`$1`) LIKE LOWER(?) ESCAPE '\\' -- \\'' \n", $statement);  // FIXME workaround for singletick matching with regexes in SQLParserUtils::getUnquotedStatementFragments
 		$statement = \str_replace('`', '"', $statement);
 		$statement = \str_ireplace('NOW()', 'CURRENT_TIMESTAMP', $statement);
 		$statement = \str_ireplace('UNIX_TIMESTAMP()', self::UNIX_TIMESTAMP_REPLACEMENT, $statement);

lib/private/DB/QueryBuilder/ExpressionBuilder/OCIExpressionBuilder.php

@@ -157,7 +157,7 @@ public function castColumn($column, $type) {
 	public function iLike($x, $y, $type = null) {
 		$x = $this->helper->quoteColumnName($x);
 		$y = $this->helper->quoteColumnName($y);
-		return new QueryFunction('REGEXP_LIKE('.$x.', \'^\' || REPLACE('.$y.', \'%\', \'.*\') || \'$\', \'i\')');
+		return new QueryFunction("LOWER($x) LIKE LOWER($y) ESCAPE '\\' -- \\'' \n"); // FIXME workaround for singletick matching with regexes in SQLParserUtils::getUnquotedStatementFragments
 	}
 
 	/**

tests/lib/Files/Cache/CacheTest.php

@@ -304,23 +304,23 @@ function testSearch() {
 		$this->cache->put($file3, $fileData['foo']);
 		$this->cache->put($file4, $fileData['f[o.o%ba-r']);
 
-		$this->assertCount(2, $this->cache->search('%foo%'));
-		$this->assertCount(1, $this->cache->search('foo'));
-		$this->assertCount(1, $this->cache->search('%folder%'));
-		$this->assertCount(1, $this->cache->search('folder%'));
-		$this->assertCount(4, $this->cache->search('%'));
+		$this->assertCount(2, $this->cache->search('%foo%'), "expected 2 when searching for '%foo%'");
+		$this->assertCount(1, $this->cache->search('foo'), "expected 1 when searching for 'foo'");
+		$this->assertCount(1, $this->cache->search('%folder%'), "expected 1 when searching for '%folder%'");
+		$this->assertCount(1, $this->cache->search('folder%'), "expected 1 when searching for 'folder%'");
+		$this->assertCount(4, $this->cache->search('%'), "expected 4 when searching for '%'");
 
 		// case insensitive search should match the same files
-		$this->assertCount(2, $this->cache->search('%Foo%'));
-		$this->assertCount(1, $this->cache->search('Foo'));
-		$this->assertCount(1, $this->cache->search('%Folder%'));
-		$this->assertCount(1, $this->cache->search('Folder%'));
+		$this->assertCount(2, $this->cache->search('%Foo%'), "expected 2 when searching for '%Foo%'");
+		$this->assertCount(1, $this->cache->search('Foo'), "expected 1 when searching for 'Foo'");
+		$this->assertCount(1, $this->cache->search('%Folder%'), "expected 1 when searching for '%Folder%'");
+		$this->assertCount(1, $this->cache->search('Folder%'), "expected 1 when searching for 'Folder%'");
 
-		$this->assertCount(4, $this->cache->searchByMime('foo'));
-		$this->assertCount(3, $this->cache->searchByMime('foo/file'));
+		$this->assertCount(4, $this->cache->searchByMime('foo'), "expected 4 when searching for mime 'foo'");
+		$this->assertCount(3, $this->cache->searchByMime('foo/file'), "expected 3 when searching for mime 'foo/file'");
 
 		// oracle uses regexp,
-		$this->assertCount(1, $this->cache->search('f[o.o%ba-r'));
+		$this->assertCount(1, $this->cache->search('f[o.o%ba-r'), "expected 1 when searching for 'f[o.o%ba-r'");
 	}
 
 	function testSearchByTag() {