Feat: add percentile_disc function

Author: taewhi

traindb-core/src/main/java/traindb/adapter/TiberoSqlDialect.java

@@ -20,6 +20,7 @@
 import org.apache.calcite.sql.SqlAlienSystemTypeNameSpec;
 import org.apache.calcite.sql.SqlDataTypeSpec;
 import org.apache.calcite.sql.SqlDialect;
+import org.apache.calcite.sql.SqlKind;
 import org.apache.calcite.sql.SqlNode;
 import org.apache.calcite.sql.SqlWriter;
 import org.apache.calcite.sql.parser.SqlParserPos;
@@ -49,6 +50,22 @@ public SqlDialect getDefaultSqlDialect() {
  return DEFAULT;
  }
 
+ @Override
+ public boolean supportsAggregateFunction(SqlKind kind) {
+ switch (kind) {
+ case COUNT:
+ case SUM:
+ case SUM0:
+ case MIN:
+ case MAX:
+ case PERCENTILE_DISC:
+ return true;
+ default:
+ break;
+ }
+ return false;
+ }
+
  @Override
  public boolean supportCatalogs() {
  return false;

traindb-core/src/main/java/traindb/adapter/jdbc/JdbcRules.java

@@ -63,7 +63,12 @@
 import org.apache.calcite.schema.ModifiableTable;
 import org.apache.calcite.sql.SqlDialect;
 import org.apache.calcite.sql.SqlFunction;
+import org.apache.calcite.sql.SqlKind;
 import org.apache.calcite.sql.SqlOperator;
+import org.apache.calcite.sql.dialect.Db2SqlDialect;
+import org.apache.calcite.sql.dialect.MssqlSqlDialect;
+import org.apache.calcite.sql.dialect.OracleSqlDialect;
+import org.apache.calcite.sql.dialect.PostgresqlSqlDialect;
 import org.apache.calcite.sql.validate.SqlValidatorUtil;
 import org.apache.calcite.tools.RelBuilder;
 import org.apache.calcite.tools.RelBuilderFactory;
@@ -663,6 +668,14 @@ protected JdbcAggregateRule(Config config) {
  * function. */
  private static boolean canImplement(AggregateCall aggregateCall,
  SqlDialect sqlDialect) {
+ if (aggregateCall.getAggregation().getKind() == SqlKind.PERCENTILE_DISC) {
+ if (sqlDialect instanceof PostgresqlSqlDialect
+ || sqlDialect instanceof Db2SqlDialect
+ || sqlDialect instanceof MssqlSqlDialect
+ || sqlDialect instanceof OracleSqlDialect) {
+ return true;
+ }
+ }
  return sqlDialect.supportsAggregateFunction(
  aggregateCall.getAggregation().getKind())
  && aggregateCall.distinctKeys == null;

traindb-core/src/main/java/traindb/planner/rules/ApproxAggregateUtil.java

@@ -56,7 +56,8 @@ public class ApproxAggregateUtil {
  "CORR",
  "MAX",
  "MIN",
- "MODE"
+ "MODE",
+ "PERCENTILE_DISC"
  );
 
  private static final List<String> scalingAggregateFuncList = Arrays.asList(