Revert "[Coral-Trino] Cast char fields, if necessary, to varchar type…

… in the set operation (linkedin#442)"

This reverts commit 4bb38a1.

# Conflicts:
#	coral-trino/src/main/java/com/linkedin/coral/trino/rel2trino/DataTypeDerivedSqlCallConverter.java

coral-common/src/main/java/com/linkedin/coral/common/transformers/SqlCallTransformer.java

@@ -5,8 +5,6 @@
  */
 package com.linkedin.coral.common.transformers;
 
-import java.util.List;
-
 import com.google.common.collect.ImmutableList;
 
 import org.apache.calcite.rel.type.RelDataType;
@@ -68,10 +66,6 @@ protected RelDataType deriveRelDatatype(SqlNode sqlNode) {
     return typeDerivationUtil.getRelDataType(sqlNode);
   }
 
-  protected RelDataType leastRestrictive(List<RelDataType> types) {
-    return typeDerivationUtil.leastRestrictive(types);
-  }
-
   /**
    * This function creates a {@link SqlOperator} for a function with the function name and return type inference.
    */

coral-common/src/main/java/com/linkedin/coral/common/utils/TypeDerivationUtil.java

@@ -93,10 +93,6 @@ public RelDataType getRelDataType(SqlNode sqlNode) {
         sqlNode, topSelectNodes.get(0)));
   }
 
-  public RelDataType leastRestrictive(List<RelDataType> types) {
-    return sqlValidator.getTypeFactory().leastRestrictive(types);
-  }
-
   private class SqlNodePreprocessorForTypeDerivation extends SqlShuttle {
     @Override
     public SqlNode visit(SqlCall sqlCall) {

coral-trino/src/main/java/com/linkedin/coral/trino/rel2trino/DataTypeDerivedSqlCallConverter.java

@@ -22,7 +22,6 @@
 import com.linkedin.coral.trino.rel2trino.transformers.GenericProjectTransformer;
 import com.linkedin.coral.trino.rel2trino.transformers.NamedStructToCastTransformer;
 import com.linkedin.coral.trino.rel2trino.transformers.SubstrOperatorTransformer;
-import com.linkedin.coral.trino.rel2trino.transformers.UnionSqlCallTransformer;
 
 
 /**
@@ -45,7 +44,7 @@ public DataTypeDerivedSqlCallConverter(HiveMetastoreClient mscClient, SqlNode to
     operatorTransformerList = SqlCallTransformers.of(new FromUtcTimestampOperatorTransformer(typeDerivationUtil),
         new GenericProjectTransformer(typeDerivationUtil), new NamedStructToCastTransformer(typeDerivationUtil),
         new ConcatOperatorTransformer(typeDerivationUtil), new SubstrOperatorTransformer(typeDerivationUtil),
-        new CastOperatorTransformer(typeDerivationUtil), new UnionSqlCallTransformer(typeDerivationUtil));
+        new CastOperatorTransformer(typeDerivationUtil));
   }
 
   @Override

coral-trino/src/test/java/com/linkedin/coral/trino/rel2trino/HiveToTrinoConverterTest.java

@@ -193,50 +193,7 @@ public Object[][] viewTestCasesProvider() {
             + "FROM \"test\".\"duplicate_column_name_a\" AS \"duplicate_column_name_a\"\n"
             + "LEFT JOIN (SELECT TRIM(\"duplicate_column_name_b\".\"some_id\") AS \"SOME_ID\", CAST(TRIM(\"duplicate_column_name_b\".\"some_id\") AS VARCHAR(65536)) AS \"$f1\"\n"
             + "FROM \"test\".\"duplicate_column_name_b\" AS \"duplicate_column_name_b\") AS \"t\" ON \"duplicate_column_name_a\".\"some_id\" = \"t\".\"$f1\") AS \"t0\"\n"
-            + "WHERE \"t0\".\"some_id\" <> ''" },
-
-        { "test", "view_char_different_size_in_union", "SELECT CAST(\"table_with_mixed_columns\".\"a_char1\" AS VARCHAR(255)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT CAST(\"table_with_mixed_columns0\".\"a_char255\" AS VARCHAR(255)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" },
-
-        { "test", "view_cast_char_to_varchar", "SELECT CAST(\"table_with_mixed_columns\".\"a_char1\" AS VARCHAR(65535)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"" },
-
-        { "test", "view_cast_char_to_varchar_in_union", "SELECT CAST(\"table_with_mixed_columns\".\"a_char1\" AS VARCHAR(65535)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT CAST(CASE WHEN \"table_with_mixed_columns0\".\"a_char1\" IS NOT NULL THEN \"table_with_mixed_columns0\".\"a_char1\" ELSE 'N' END AS VARCHAR(65535)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" },
-
-        { "test", "view_cast_char_to_varchar_in_union_flipped", "SELECT CAST(CASE WHEN \"table_with_mixed_columns\".\"a_char1\" IS NOT NULL THEN \"table_with_mixed_columns\".\"a_char1\" ELSE 'N' END AS VARCHAR(65535)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT CAST(\"table_with_mixed_columns0\".\"a_char1\" AS VARCHAR(65535)) AS \"col\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" },
-
-        { "test", "view_cast_char_to_varchar_with_other_fields_in_union", "SELECT CAST(\"table_with_mixed_columns\".\"a_char1\" AS VARCHAR(65535)) AS \"text\", \"table_with_mixed_columns\".\"a_boolean\" AS \"a_boolean\", \"table_with_mixed_columns\".\"a_smallint\" AS \"a_number\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT CAST(CASE WHEN \"table_with_mixed_columns0\".\"a_char1\" IS NOT NULL THEN \"table_with_mixed_columns0\".\"a_char1\" ELSE 'N' END AS VARCHAR(65535)) AS \"text\", \"table_with_mixed_columns0\".\"a_boolean\" AS \"a_boolean\", \"table_with_mixed_columns0\".\"a_integer\" AS \"a_number\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" },
-
-        { "test", "view_char_and_null_in_union", "SELECT \"table_with_mixed_columns\".\"a_char1\" AS \"text\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT NULL AS \"text\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" },
-
-        { "test", "view_different_numerical_types_in_union", "SELECT *\n" + "FROM (SELECT *\n"
-            + "FROM (SELECT \"table_with_mixed_columns\".\"a_tinyint\" AS \"a_number\", \"table_with_mixed_columns\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT \"table_with_mixed_columns0\".\"a_smallint\" AS \"a_number\", \"table_with_mixed_columns0\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\") AS \"t1\"\n" + "UNION ALL\n"
-            + "SELECT \"table_with_mixed_columns1\".\"a_integer\" AS \"a_number\", \"table_with_mixed_columns1\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns1\") AS \"t3\"\n" + "UNION ALL\n"
-            + "SELECT \"table_with_mixed_columns2\".\"a_bigint\" AS \"a_number\", \"table_with_mixed_columns2\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns2\"" },
-
-        { "test", "view_union_no_casting", "SELECT \"table_with_mixed_columns\".\"a_tinyint\" AS \"a_tinyint\", \"table_with_mixed_columns\".\"a_smallint\" AS \"a_smallint\", \"table_with_mixed_columns\".\"a_integer\" AS \"a_integer\", \"table_with_mixed_columns\".\"a_bigint\" AS \"a_bigint\", \"table_with_mixed_columns\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns\"\n" + "UNION ALL\n"
-            + "SELECT \"table_with_mixed_columns0\".\"a_tinyint\" AS \"a_tinyint\", \"table_with_mixed_columns0\".\"a_smallint\" AS \"a_smallint\", \"table_with_mixed_columns0\".\"a_integer\" AS \"a_integer\", \"table_with_mixed_columns0\".\"a_bigint\" AS \"a_bigint\", \"table_with_mixed_columns0\".\"a_float\" AS \"a_float\"\n"
-            + "FROM \"test\".\"table_with_mixed_columns\" AS \"table_with_mixed_columns0\"" } };
+            + "WHERE \"t0\".\"some_id\" <> ''" } };
   }
 
   @Test

coral-trino/src/test/java/com/linkedin/coral/trino/rel2trino/TestUtils.java

@@ -377,42 +377,6 @@ public static void initializeTablesAndViews(HiveConf conf) throws HiveException,
 
     run(driver, "CREATE TABLE test.table_with_binary_column (b binary)");
 
-    run(driver,
-        "CREATE TABLE test.table_with_mixed_columns (a_char1 char(1), a_char255 char(255), a_string string, a_tinyint tinyint, a_smallint smallint, a_integer int, a_bigint bigint, a_float float, a_double double, a_boolean boolean)");
-    run(driver, "CREATE VIEW IF NOT EXISTS test.view_cast_char_to_varchar AS \n"
-        + "SELECT CAST(a_char1 AS VARCHAR(65535)) AS col FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_char_different_size_in_union AS \n"
-            + "SELECT a_char1 AS col FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT a_char255 AS col FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_cast_char_to_varchar_in_union AS \n"
-            + "SELECT CAST(a_char1 AS VARCHAR(65535)) AS col FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT COALESCE(a_char1, 'N') AS  col FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_cast_char_to_varchar_in_union_flipped AS \n"
-            + "SELECT COALESCE(a_char1, 'N') as  col FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT CAST(a_char1 AS VARCHAR(65535)) AS col FROM test.table_with_mixed_columns");
-    run(driver, "CREATE VIEW IF NOT EXISTS test.view_cast_char_to_varchar_with_other_fields_in_union AS \n"
-        + "SELECT CAST(a_char1 AS VARCHAR(65535)) AS text , a_boolean, a_smallint as a_number FROM test.table_with_mixed_columns \n"
-        + "UNION ALL\n"
-        + "SELECT COALESCE(a_char1, 'N') as  text, a_boolean, a_integer as a_number FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_char_and_null_in_union AS \n"
-            + "SELECT a_char1 as text FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT NULL  text FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_different_numerical_types_in_union AS \n"
-            + "SELECT a_tinyint AS a_number, a_float FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT a_smallint AS a_number, a_float FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT a_integer AS a_number, a_float FROM test.table_with_mixed_columns \n" + "UNION ALL\n"
-            + "SELECT a_bigint AS a_number, a_float FROM test.table_with_mixed_columns");
-    run(driver,
-        "CREATE VIEW IF NOT EXISTS test.view_union_no_casting AS \n"
-            + "SELECT a_tinyint, a_smallint, a_integer, a_bigint, a_float FROM test.table_with_mixed_columns \n"
-            + "UNION ALL\n"
-            + "SELECT a_tinyint, a_smallint, a_integer, a_bigint, a_float FROM test.table_with_mixed_columns");
-
     // Tables used in RelToTrinoConverterTest
     run(driver,
         "CREATE TABLE IF NOT EXISTS test.tableOne(icol int, dcol double, scol string, tcol timestamp, acol array<string>)");