Enable case-sensitive identifier support for BigQuery connector

Author: adkharat

presto-bigquery/src/main/java/com/facebook/presto/plugin/bigquery/BigQueryClient.java

@@ -50,6 +50,7 @@ public class BigQueryClient
     private final Optional<String> viewMaterializationProject;
     private final Optional<String> viewMaterializationDataset;
     private final String tablePrefix = "_pbc_";
+    private final boolean caseSensitiveNameMatching;
 
     // presto converts the dataset and table names to lower case, while BigQuery is case sensitive
     private final ConcurrentMap<TableId, TableId> tableIds = new ConcurrentHashMap<>();
@@ -60,6 +61,7 @@ public class BigQueryClient
         this.bigQuery = requireNonNull(bigQuery, "bigQuery is null");
         this.viewMaterializationProject = requireNonNull(config.getViewMaterializationProject(), "viewMaterializationProject is null");
         this.viewMaterializationDataset = requireNonNull(config.getViewMaterializationDataset(), "viewMaterializationDataset is null");
+        this.caseSensitiveNameMatching = config.isCaseSensitiveNameMatching();
     }
 
     public TableInfo getTable(TableId tableId)
@@ -108,7 +110,7 @@ private void addTableMappingIfNeeded(DatasetId datasetID, Table table)
     private Dataset addDataSetMappingIfNeeded(Dataset dataset)
     {
         DatasetId bigQueryDatasetId = dataset.getDatasetId();
-        DatasetId prestoDatasetId = DatasetId.of(bigQueryDatasetId.getProject(), bigQueryDatasetId.getDataset().toLowerCase(ENGLISH));
+        DatasetId prestoDatasetId = DatasetId.of(bigQueryDatasetId.getProject(), bigQueryDatasetId.getDataset());
         datasetIds.putIfAbsent(prestoDatasetId, bigQueryDatasetId);
         return dataset;
     }
@@ -123,7 +125,8 @@ protected TableId createDestinationTable(TableId tableId)
 
     private String createTableName()
     {
-        return format(tablePrefix + "%s", randomUUID().toString().toLowerCase(ENGLISH).replace("-", ""));
+        String uuid = randomUUID().toString().replace("-", "");
+        return caseSensitiveNameMatching ? format("%s%s", tablePrefix, uuid) : format("%s%s", tablePrefix, uuid).toLowerCase(ENGLISH);
     }
 
     private DatasetId mapIfNeeded(String project, String dataset)

presto-bigquery/src/main/java/com/facebook/presto/plugin/bigquery/BigQueryConfig.java

@@ -35,6 +35,7 @@ public class BigQueryConfig
     private Optional<String> parentProjectId = Optional.empty();
     private OptionalInt parallelism = OptionalInt.empty();
     private boolean viewsEnabled;
+    private boolean caseSensitiveNameMatching;
     private Optional<String> viewMaterializationProject = Optional.empty();
     private Optional<String> viewMaterializationDataset = Optional.empty();
     private int maxReadRowsRetries = DEFAULT_MAX_READ_ROWS_RETRIES;
@@ -181,6 +182,22 @@ public BigQueryConfig setMaxReadRowsRetries(int maxReadRowsRetries)
         return this;
     }
 
+    public boolean isCaseSensitiveNameMatching()
+    {
+        return caseSensitiveNameMatching;
+    }
+
+    @Config("case-sensitive-name-matching")
+    @ConfigDescription(
+            "Case sensitivity for schema and table name matching. " +
+             "true = preserve case and require exact matches; " +
+             "false (default) = normalize to lower case and match case-insensitively.")
+    public BigQueryConfig setCaseSensitiveNameMatching(boolean caseSensitiveNameMatching)
+    {
+        this.caseSensitiveNameMatching = caseSensitiveNameMatching;
+        return this;
+    }
+
     ReadSessionCreatorConfig createReadSessionCreatorConfig()
     {
         return new ReadSessionCreatorConfig(

presto-bigquery/src/main/java/com/facebook/presto/plugin/bigquery/BigQueryMetadata.java

@@ -51,6 +51,7 @@
 import static com.google.cloud.bigquery.TableDefinition.Type.TABLE;
 import static com.google.cloud.bigquery.TableDefinition.Type.VIEW;
 import static com.google.common.collect.ImmutableList.toImmutableList;
+import static java.util.Locale.ENGLISH;
 import static java.util.Objects.requireNonNull;
 import static java.util.stream.Collectors.toMap;
 
@@ -63,12 +64,14 @@ public class BigQueryMetadata
     private static final Logger log = Logger.get(BigQueryMetadata.class);
     private final BigQueryClient bigQueryClient;
     private final String projectId;
+    private final boolean caseSensitiveNameMatching;
 
     @Inject
     public BigQueryMetadata(BigQueryClient bigQueryClient, BigQueryConfig config)
     {
         this.bigQueryClient = bigQueryClient;
         this.projectId = config.getProjectId().orElse(bigQueryClient.getProjectId());
+        this.caseSensitiveNameMatching = config.isCaseSensitiveNameMatching();
     }
 
     @Override
@@ -233,4 +236,10 @@ private List<SchemaTableName> listTables(ConnectorSession session, SchemaTablePr
                 ImmutableList.of(tableName) :
                 ImmutableList.of(); // table does not exist
     }
+
+    @Override
+    public String normalizeIdentifier(ConnectorSession session, String identifier)
+    {
+        return caseSensitiveNameMatching ? identifier : identifier.toLowerCase(ENGLISH);
+    }
 }

presto-bigquery/src/test/java/com/facebook/presto/plugin/bigquery/TestBigQueryConfig.java

@@ -36,7 +36,8 @@ public void testDefaults()
                 .setParallelism(20)
                 .setViewMaterializationProject("vmproject")
                 .setViewMaterializationDataset("vmdataset")
-                .setMaxReadRowsRetries(10);
+                .setMaxReadRowsRetries(10)
+                .setCaseSensitiveNameMatching(false);
 
         assertEquals(config.getCredentialsKey(), Optional.of("ckey"));
         assertEquals(config.getCredentialsFile(), Optional.of("cfile"));
@@ -46,6 +47,7 @@ public void testDefaults()
         assertEquals(config.getViewMaterializationProject(), Optional.of("vmproject"));
         assertEquals(config.getViewMaterializationDataset(), Optional.of("vmdataset"));
         assertEquals(config.getMaxReadRowsRetries(), 10);
+        assertEquals(config.isCaseSensitiveNameMatching(), false);
     }
 
     @Test
@@ -59,6 +61,7 @@ public void testExplicitPropertyMappingsWithCredentialsKey()
                 .put("bigquery.view-materialization-project", "vmproject")
                 .put("bigquery.view-materialization-dataset", "vmdataset")
                 .put("bigquery.max-read-rows-retries", "10")
+                .put("case-sensitive-name-matching", "true")
                 .build();
 
         ConfigurationFactory configurationFactory = new ConfigurationFactory(properties);
@@ -71,6 +74,7 @@ public void testExplicitPropertyMappingsWithCredentialsKey()
         assertEquals(config.getViewMaterializationProject(), Optional.of("vmproject"));
         assertEquals(config.getViewMaterializationDataset(), Optional.of("vmdataset"));
         assertEquals(config.getMaxReadRowsRetries(), 10);
+        assertEquals(config.isCaseSensitiveNameMatching(), true);
     }
 
     @Test

presto-docs/src/main/sphinx/connector/bigquery.rst

@@ -137,6 +137,9 @@ Property                                  Description
 ``bigquery.max-read-rows-retries``        The number of retries in case of retryable server issues       ``3``
 ``bigquery.credentials-key``              credentials key (base64 encoded)                               None. See `authentication <#authentication>`_
 ``bigquery.credentials-file``             JSON credentials file path                                     None. See `authentication <#authentication>`_
+``case-sensitive-name-matching``          Enable case sensitive identifier support for schema and table  ``false``
+                                          names for the connector. When disabled, names are matched
+                                          case-insensitively using lowercase normalization.          
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 Data Types