Refine default cursor preference when using FOR JSON/FOR XML.

We now no longer prefer cursor usage by default when the statement ends with a FOR XML/JSON clause to avoid server side errors reporting that cursor usage is not supported.

[resolves #209]

Signed-off-by: Mark Paluch <[email protected]>

Author: mp911de

src/main/java/io/r2dbc/mssql/SimpleMssqlStatement.java

@@ -174,9 +174,14 @@ static boolean prefersCursors(String sql) {
             return false;
         }
 
+        String lc = sql.trim().toLowerCase(Locale.ENGLISH);
+        if (lc.contains("for xml") || lc.contains("for json")) {
+            return false;
+        }
+
         char c = sql.charAt(0);
 
-        return (c == 's' || c == 'S') && sql.toLowerCase(Locale.ENGLISH).startsWith("select");
+        return (c == 's' || c == 'S') && lc.startsWith("select");
     }
 
 }

src/test/java/io/r2dbc/mssql/JsonIntegrationTests.java

@@ -30,7 +30,7 @@ class JsonIntegrationTests extends IntegrationTestSupport {
     @Test
     void shouldExecuteForJsonSimple() {
 
-        connection.createStatement("select 1 as a for json path").fetchSize(0).execute()
+        connection.createStatement("select 1 as a for json path").execute()
             .flatMap(result -> result.map((row, rowMetadata) -> row.get(0)))
             .as(StepVerifier::create)
             .expectNext("[{\"a\":1}]")

src/test/java/io/r2dbc/mssql/XmlIntegrationTests.java

@@ -30,7 +30,7 @@ class XmlIntegrationTests extends IntegrationTestSupport {
     @Test
     void shouldExecuteForXmlSimple() {
 
-        connection.createStatement("select 1 as a for xml path").fetchSize(0).execute()
+        connection.createStatement("select 1 as a for xml path").execute()
             .flatMap(result -> result.map((row, rowMetadata) -> row.get(0)))
             .as(StepVerifier::create)
             .expectNext("<row><a>1</a></row>")