Add Synonyms to SqlServerConnector

docs/src/main/sphinx/connector/sqlserver.md

@@ -106,6 +106,10 @@ behavior of the connector and the issues queries to the database.
   - Control the automatic use of snapshot isolation for transactions issued by
       Trino in SQL Server. Defaults to `false`, which means that snapshot
       isolation is enabled.
+* - `sqlserver.synonyms.enabled=true`
+  - Include [synonyms](https://learn.microsoft.com/en-us/sql/relational-databases/synonyms/synonyms-database-engine?view=sql-server-ver16)
+      as queryable entities. Defaults to `false`, which means synonyms are not
+      included by default.
 :::
 
 ```{include} jdbc-case-insensitive-matching.fragment

plugin/trino-sqlserver/src/main/java/io/trino/plugin/sqlserver/SqlServerClient.java

@@ -287,10 +287,12 @@ public class SqlServerClient
 
         return FULL_PUSHDOWN.apply(session, domain);
     };
+    private final boolean synonymsEnabled;
 
     @Inject
     public SqlServerClient(
             BaseJdbcConfig config,
+            SqlServerConfig sqlServerConfig,
             JdbcStatisticsConfig statisticsConfig,
             ConnectionFactory connectionFactory,
             QueryBuilder queryBuilder,
@@ -300,6 +302,7 @@ public SqlServerClient(
         super("\"", connectionFactory, queryBuilder, config.getJdbcTypesMappedToVarchar(), identifierMapping, queryModifier, true);
 
         this.statisticsEnabled = statisticsConfig.isEnabled();
+        this.synonymsEnabled = sqlServerConfig.isSynonymsEnabled();
 
         this.connectorExpressionRewriter = JdbcConnectorExpressionRewriterBuilder.newBuilder()
                 .addStandardRules(this::quoted)
@@ -345,6 +348,15 @@ public SqlServerClient(
                         .build());
     }
 
+    @Override
+    protected Optional<List<String>> getTableTypes()
+    {
+        if (synonymsEnabled) {
+            return Optional.of(ImmutableList.of("TABLE", "VIEW", "SYNONYM"));
+        }
+        return Optional.of(ImmutableList.of("TABLE", "VIEW"));
+    }
+
     @Override
     protected void dropSchema(ConnectorSession session, Connection connection, String remoteSchemaName, boolean cascade)
             throws SQLException

plugin/trino-sqlserver/src/main/java/io/trino/plugin/sqlserver/SqlServerConfig.java

@@ -23,6 +23,7 @@ public class SqlServerConfig
     private boolean bulkCopyForWrite;
     private boolean bulkCopyForWriteLockDestinationTable;
     private boolean storedProcedureTableFunctionEnabled;
+    private boolean synonymsEnabled;
 
     public boolean isBulkCopyForWrite()
     {
@@ -76,4 +77,17 @@ public SqlServerConfig setStoredProcedureTableFunctionEnabled(boolean storedProc
         this.storedProcedureTableFunctionEnabled = storedProcedureTableFunctionEnabled;
         return this;
     }
+
+    @Config("sqlserver.synonyms.enabled")
+    @ConfigDescription("Allows SQL Server Synonym manipulation")
+    public SqlServerConfig setSynonymsEnabled(boolean enabled)
+    {
+        this.synonymsEnabled = enabled;
+        return this;
+    }
+
+    public boolean isSynonymsEnabled()
+    {
+        return synonymsEnabled;
+    }
 }

plugin/trino-sqlserver/src/test/java/io/trino/plugin/sqlserver/BaseSqlServerConnectorTest.java

@@ -120,6 +120,14 @@ public void testReadFromView()
         }
     }
 
+    @Test
+    public void testSynonyms()
+    {
+        try (TestSynonym synonym = new TestSynonym(onRemoteDatabase(), "test_synonym", "FOR ORDERS")) {
+            assertQueryFails("SELECT orderkey FROM " + synonym.getName(), "line 1:22: Table 'sqlserver.*' does not exist");
+        }
+    }
+
     @Override
     protected void verifyAddNotNullColumnToNonEmptyTableFailurePermissible(Throwable e)
     {

plugin/trino-sqlserver/src/test/java/io/trino/plugin/sqlserver/TestSqlServerClient.java

@@ -58,6 +58,7 @@ public class TestSqlServerClient
 
     private static final JdbcClient JDBC_CLIENT = new SqlServerClient(
             new BaseJdbcConfig(),
+            new SqlServerConfig(),
             new JdbcStatisticsConfig(),
             session -> {
                 throw new UnsupportedOperationException();

plugin/trino-sqlserver/src/test/java/io/trino/plugin/sqlserver/TestSqlServerConfig.java

@@ -28,6 +28,7 @@ public class TestSqlServerConfig
     public void testDefaults()
     {
         assertRecordedDefaults(recordDefaults(SqlServerConfig.class)
+                .setSynonymsEnabled(false)
                 .setBulkCopyForWrite(false)
                 .setBulkCopyForWriteLockDestinationTable(false)
                 .setSnapshotIsolationDisabled(false)
@@ -38,13 +39,15 @@ public void testDefaults()
     public void testExplicitPropertyMappings()
     {
         Map<String, String> properties = ImmutableMap.<String, String>builder()
+                .put("sqlserver.synonyms.enabled", "true")
                 .put("sqlserver.bulk-copy-for-write.enabled", "true")
                 .put("sqlserver.bulk-copy-for-write.lock-destination-table", "true")
                 .put("sqlserver.snapshot-isolation.disabled", "true")
                 .put("sqlserver.stored-procedure-table-function-enabled", "true")
                 .buildOrThrow();
 
         SqlServerConfig expected = new SqlServerConfig()
+                .setSynonymsEnabled(true)
                 .setBulkCopyForWrite(true)
                 .setBulkCopyForWriteLockDestinationTable(true)
                 .setStoredProcedureTableFunctionEnabled(true)

plugin/trino-sqlserver/src/test/java/io/trino/plugin/sqlserver/TestSynonym.java

@@ -0,0 +1,46 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.trino.plugin.sqlserver;
+
+import io.trino.testing.sql.SqlExecutor;
+
+import java.io.Closeable;
+
+import static io.trino.testing.TestingNames.randomNameSuffix;
+import static java.lang.String.format;
+
+public class TestSynonym
+        implements Closeable
+{
+    private final SqlExecutor sqlExecutor;
+    private final String name;
+
+    public TestSynonym(SqlExecutor sqlExecutor, String namePrefix, String definition)
+    {
+        this.sqlExecutor = sqlExecutor;
+        this.name = namePrefix + "_" + randomNameSuffix();
+        sqlExecutor.execute(format("CREATE SYNONYM %s %s", name, definition));
+    }
+
+    public String getName()
+    {
+        return name;
+    }
+
+    @Override
+    public void close()
+    {
+        sqlExecutor.execute("DROP SYNONYM " + name);
+    }
+}