Issue #308

source/shared/core_stmt.cpp

@@ -2007,7 +2007,12 @@ void finalize_output_parameters( sqlsrv_stmt* stmt TSRMLS_DC )
             // adjust the length of the string to the value returned by SQLBindParameter in the ind_ptr parameter
             char* str = Z_STRVAL_P( value_z );
             SQLLEN str_len = stmt->param_ind_ptrs[ output_param->param_num ];
-            if( str_len == SQL_NULL_DATA || str_len == 0 ) {
+			if (str_len == 0) {
+				str[str_len] = '\0';
+				core::sqlsrv_zval_stringl( value_z, str, str_len );
+				continue;
+			}
+            if( str_len == SQL_NULL_DATA ) {
                 zend_string_release( Z_STR_P( value_z ));
                 ZVAL_NULL( value_z );
                 continue;

test/pdo_sqlsrv/pdo_308_empty_output_param.phpt

@@ -0,0 +1,46 @@
+--TEST--
+GitHub issue #308 - empty string set to output parameter on stored procedure 
+--SKIPIF--
+--FILE--
+<?php
+require_once("pdo_tools.inc");
+
+// Connect 
+require_once("autonomous_setup.php");
+
+$dbName = "tempdb";
+
+$conn = new PDO("sqlsrv:server=$serverName;Database=$dbName", $username, $password);   
+$conn->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );   
+
+$procName = GetTempProcName();
+
+$sql = "CREATE PROCEDURE $procName @TEST VARCHAR(200)='' OUTPUT
+AS BEGIN
+SET NOCOUNT ON;
+SET @TEST='';
+SELECT HELLO_WORLD_COLUMN='THIS IS A COLUMN IN A SINGLE DATASET';
+END";
+$stmt = $conn->exec($sql);
+
+$sql = "EXEC $procName @Test = :Test";
+$stmt = $conn->prepare($sql);
+$out = '';
+$stmt->bindParam(':Test', $out, PDO::PARAM_STR | PDO::PARAM_INPUT_OUTPUT, 200);
+$stmt->execute();
+
+$result = $stmt->fetchAll();
+$stmt->closeCursor();
+
+echo "OUT value: ";
+var_dump($out);
+
+// Free the statement and connection resources. 
+$stmt = null;
+$conn = null;
+
+print "Done";
+?> 
+--EXPECT--
+OUT value: string(0) ""
+Done