Del REGEXP SqlKind

Author: Terran

core/src/main/java/org/apache/calcite/sql/SqlKind.java

@@ -1357,10 +1357,7 @@ public enum SqlKind {
    * commands for them. Use OTHER_DDL in the short term, but we are happy to add
    * new enum values for your object types. Just ask!
    */
-  OTHER_DDL,
-
-  /** The {@code REGEXP} function. */
-  REGEXP;
+  OTHER_DDL;
 
   //~ Static fields/initializers ---------------------------------------------
 

core/src/main/java/org/apache/calcite/sql/dialect/HiveSqlDialect.java

@@ -129,7 +129,7 @@ public HiveSqlDialect(Context context) {
     case TRIM:
       RelToSqlConverterUtil.unparseHiveTrim(writer, call, leftPrec, rightPrec);
       break;
-    case REGEXP:
+    case RLIKE:
       RelToSqlConverterUtil.unparseRegexp(writer, call, leftPrec, rightPrec);
       break;
     default:

core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java

@@ -707,7 +707,7 @@ static RelDataType deriveTypeSplit(SqlOperatorBinding operatorBinding,
   /** The "REGEXP(value, regexp)" function, equivalent to {@link #RLIKE}. */
   @LibraryOperator(libraries = {SPARK, HIVE})
   public static final SqlFunction REGEXP =
-      SqlBasicFunction.create(SqlKind.REGEXP, ReturnTypes.BOOLEAN_NULLABLE,
+      SqlBasicFunction.create("REGEXP", SqlKind.RLIKE, ReturnTypes.BOOLEAN_NULLABLE,
           OperandTypes.STRING_STRING);
 
   /** The "REGEXP_LIKE(value, regexp)" function, equivalent to {@link #RLIKE}. */

core/src/main/java/org/apache/calcite/util/RelToSqlConverterUtil.java

@@ -454,12 +454,13 @@ public static void unparseRegexp(SqlWriter writer, SqlCall call, int leftPrec, i
     if (call.operandCount() != 2) {
       throw new IllegalArgumentException("REGEXP operator requires exactly 2 operands");
     }
-
-    final SqlWriter.Frame frame = writer.startList(SqlWriter.FrameTypeEnum.SIMPLE, "(", ")");
-    call.operand(0).unparse(writer, leftPrec, rightPrec);
-    writer.sep("REGEXP", true);
-    call.operand(1).unparse(writer, leftPrec, rightPrec);
-    writer.endList(frame);
+    if ("REGEXP".equals(call.getOperator().getName())) {
+      final SqlWriter.Frame frame = writer.startList(SqlWriter.FrameTypeEnum.SIMPLE, "(", ")");
+      call.operand(0).unparse(writer, leftPrec, rightPrec);
+      writer.sep("REGEXP", true);
+      call.operand(1).unparse(writer, leftPrec, rightPrec);
+      writer.endList(frame);
+    }
   }
 
 }