add oracle limit push down

Author: chngpe

athena-federation-sdk/src/main/java/com/amazonaws/athena/connector/lambda/resolver/CaseResolver.java

@@ -46,11 +46,11 @@ public CaseResolver(String sourceType, FederationSDKCasingMode nonGlueBasedDefau
 
     public enum FederationSDKCasingMode
     {
-        NONE,
+        NONE,       // casing mode to ignore adjustment.
         LOWER,      // casing mode to lower case everything (glue and trino lower case everything)
         UPPER,      // casing mode to upper case everything (oracle by default upper cases everything)
-        CASE_INSENSITIVE_SEARCH, //
-        ANNOTATION
+        CASE_INSENSITIVE_SEARCH, // casing mode to perform case_insensitive_search mode
+        ANNOTATION // casing mode to use annotation (legacy) in query
     }
 
     protected final FederationSDKCasingMode getCasingMode(Map<String, String> configOptions)

athena-jdbc/src/main/java/com/amazonaws/athena/connectors/jdbc/connection/GenericJdbcConnectionFactory.java

@@ -32,7 +32,7 @@
 import java.io.UnsupportedEncodingException;
 import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
-import java.sql.Connection;;
+import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.Map;
 import java.util.Properties;

athena-oracle/src/main/java/com/amazonaws/athena/connectors/oracle/OracleQueryStringBuilder.java

@@ -76,6 +76,6 @@ protected List<String> getPartitionWhereClauses(final Split split)
     @Override
     protected String appendLimitOffset(Split split, Constraints constraints)
     {
-        return emptyString;
+        return String.format(" FETCH FIRST %d ROWS ONLY ", constraints.getLimit());
     }
 }

athena-oracle/src/test/java/com/amazonaws/athena/connectors/oracle/OracleRecordHandlerTest.java

@@ -145,7 +145,7 @@ public void buildSplitSql()
 
         Mockito.when(constraints.getLimit()).thenReturn(5L);
 
-        String expectedSql = "SELECT \"testCol1\", \"testCol2\", \"testCol3\", \"testCol4\", \"testCol5\", \"testCol6\", \"testCol7\", \"testCol8\", \"testCol9\", \"testCol10\" FROM \"testSchema\".\"testTable\" PARTITION (p0)  WHERE (\"testCol1\" IN (?,?)) AND ((\"testCol2\" >= ? AND \"testCol2\" < ?)) AND ((\"testCol3\" > ? AND \"testCol3\" <= ?)) AND (\"testCol4\" = ?) AND (\"testCol5\" = ?) AND (\"testCol6\" = ?) AND (\"testCol7\" = ?) AND (\"testCol8\" = ?) AND (\"testCol9\" = ?) AND (\"testCol10\" = ?)";
+        String expectedSql = "SELECT \"testCol1\", \"testCol2\", \"testCol3\", \"testCol4\", \"testCol5\", \"testCol6\", \"testCol7\", \"testCol8\", \"testCol9\", \"testCol10\" FROM \"testSchema\".\"testTable\" PARTITION (p0)  WHERE (\"testCol1\" IN (?,?)) AND ((\"testCol2\" >= ? AND \"testCol2\" < ?)) AND ((\"testCol3\" > ? AND \"testCol3\" <= ?)) AND (\"testCol4\" = ?) AND (\"testCol5\" = ?) AND (\"testCol6\" = ?) AND (\"testCol7\" = ?) AND (\"testCol8\" = ?) AND (\"testCol9\" = ?) AND (\"testCol10\" = ?) FETCH FIRST 5 ROWS ONLY ";
         PreparedStatement expectedPreparedStatement = Mockito.mock(PreparedStatement.class);
         Mockito.when(this.connection.prepareStatement(Mockito.eq(expectedSql))).thenReturn(expectedPreparedStatement);
         PreparedStatement preparedStatement = this.oracleRecordHandler.buildSplitSql(this.connection, "testCatalogName", tableName, schema, constraints, split);