[CALCITE-7607] DML type coercion inserts implicit narrowing casts for target-column assignments

core/src/main/java/org/apache/calcite/rel/core/TableModify.java

@@ -32,7 +32,9 @@
 import org.apache.calcite.rel.metadata.RelMetadataQuery;
 import org.apache.calcite.rel.type.RelDataType;
 import org.apache.calcite.rel.type.RelDataTypeFactory;
+import org.apache.calcite.rel.type.RelDataTypeField;
 import org.apache.calcite.rex.RexNode;
+import org.apache.calcite.rex.RexUtil;
 import org.apache.calcite.sql.SqlKind;
 import org.apache.calcite.sql.type.SqlTypeUtil;
 
@@ -261,9 +263,37 @@ public boolean isMerge() {
               null);
     }
 
+    inputRowType = expectedInputRowTypeForAssignment(inputRowType);
     return inputRowType;
   }
 
+  private RelDataType expectedInputRowTypeForAssignment(
+      RelDataType expectedRowType) {
+    final RelDataType actualRowType = getInput().getRowType();
+    if (actualRowType.getFieldCount() != expectedRowType.getFieldCount()) {
+      return expectedRowType;
+    }
+    final RelDataTypeFactory typeFactory = getCluster().getTypeFactory();
+    final RelDataTypeFactory.Builder builder = typeFactory.builder();
+    boolean changed = false;
+    final List<RelDataTypeField> expectedFields = expectedRowType.getFieldList();
+    final List<RelDataTypeField> actualFields = actualRowType.getFieldList();
+    for (int i = 0; i < expectedFields.size(); i++) {
+      final RelDataTypeField expectedField = expectedFields.get(i);
+      final RelDataType actualType = actualFields.get(i).getType();
+      final RelDataType expectedType = expectedField.getType();
+      if (!SqlTypeUtil.equalSansNullability(typeFactory, actualType, expectedType)
+          && SqlTypeUtil.canAssignFrom(expectedType, actualType)
+          && !RexUtil.isLosslessCast(actualType, expectedType)) {
+        builder.add(expectedField.getName(), actualType);
+        changed = true;
+      } else {
+        builder.add(expectedField);
+      }
+    }
+    return changed ? builder.build() : expectedRowType;
+  }
+
   @Override public RelWriter explainTerms(RelWriter pw) {
     return super.explainTerms(pw)
         .item("table", table.getQualifiedName())

core/src/main/java/org/apache/calcite/sql/validate/implicit/TypeCoercionImpl.java

@@ -19,6 +19,7 @@
 import org.apache.calcite.rel.type.RelDataType;
 import org.apache.calcite.rel.type.RelDataTypeFactory;
 import org.apache.calcite.rel.type.RelDataTypeField;
+import org.apache.calcite.rex.RexUtil;
 import org.apache.calcite.sql.SqlCall;
 import org.apache.calcite.sql.SqlCallBinding;
 import org.apache.calcite.sql.SqlFunction;
@@ -830,8 +831,13 @@ && coerceOperandType(binding.getScope(), binding.getCall(), i, implicitType)
     }
     boolean coerced = false;
     for (int i = 0; i < sourceFields.size(); i++) {
+      RelDataType sourceType = sourceFields.get(i).getType();
       RelDataType targetType = targetFields.get(i).getType();
-      coerced = coerceSourceRowType(scope, query, i, targetType) || coerced;
+      if (!SqlTypeUtil.equalSansNullability(validator.getTypeFactory(), sourceType, targetType)
+          && (RexUtil.isLosslessCast(sourceType, targetType)
+              || !SqlTypeUtil.canAssignFrom(targetType, sourceType))) {
+        coerced = coerceSourceRowType(scope, query, i, targetType) || coerced;
+      }
     }
     return coerced;
   }

core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java

@@ -9932,7 +9932,7 @@ private void checkLiteral2(String expression, String expected) {
         + "ON \"DEPT\".\"DEPTNO\" = \"DEPT0\".\"DEPTNO\"\n"
         + "WHEN MATCHED THEN UPDATE SET \"DNAME\" = \"DEPT\".\"DNAME\"\n"
         + "WHEN NOT MATCHED THEN INSERT (\"DEPTNO\", \"DNAME\", \"LOC\") "
-        + "VALUES CAST(\"DEPT\".\"DEPTNO\" + 1 AS TINYINT),\n"
+        + "VALUES \"DEPT\".\"DEPTNO\" + 1,\n"
         + "LOWER(\"DEPT\".\"DNAME\"),\n"
         + "UPPER(\"DEPT\".\"LOC\")";
     sql(sql1)
@@ -9966,9 +9966,9 @@ private void checkLiteral2(String expression, String expected) {
         + "ON \"DEPT\".\"DEPTNO\" = \"DEPT0\".\"DEPTNO\"\n"
         + "WHEN MATCHED THEN UPDATE SET \"DNAME\" = \"DEPT\".\"DNAME\"\n"
         + "WHEN NOT MATCHED THEN INSERT (\"DEPTNO\", \"DNAME\", \"LOC\") "
-        + "VALUES CAST(\"DEPT\".\"DEPTNO\" + 1 AS TINYINT),\n"
+        + "VALUES \"DEPT\".\"DEPTNO\" + 1,\n"
         + "'abc',\n"
-        + "CAST(LOWER(\"DEPT\".\"DNAME\") AS VARCHAR(13) CHARACTER SET \"ISO-8859-1\")";
+        + "LOWER(\"DEPT\".\"DNAME\")";
     sql(sql3)
         .schema(CalciteAssert.SchemaSpec.JDBC_SCOTT)
         .ok(expected3);
@@ -9998,7 +9998,7 @@ private void checkLiteral2(String expression, String expected) {
         + "USING \"SCOTT\".\"DEPT\"\n"
         + "ON \"DEPT\".\"DEPTNO\" = \"DEPT0\".\"DEPTNO\"\n"
         + "WHEN NOT MATCHED THEN INSERT (\"DEPTNO\", \"DNAME\", \"LOC\") "
-        + "VALUES CAST(\"DEPT\".\"DEPTNO\" + 1 AS TINYINT),\n"
+        + "VALUES \"DEPT\".\"DEPTNO\" + 1,\n"
         + "LOWER(\"DEPT\".\"DNAME\"),\n"
         + "UPPER(\"DEPT\".\"LOC\")";
     sql(sql5)
@@ -10018,7 +10018,7 @@ private void checkLiteral2(String expression, String expected) {
         + "WHERE CAST(\"DEPTNO\" AS INTEGER) <> 5) AS \"t0\"\n"
         + "ON \"t0\".\"DEPTNO\" = \"DEPT0\".\"DEPTNO\"\n"
         + "WHEN NOT MATCHED THEN INSERT (\"DEPTNO\", \"DNAME\", \"LOC\") "
-        + "VALUES CAST(\"t0\".\"DEPTNO\" + 1 AS TINYINT),\n"
+        + "VALUES \"t0\".\"DEPTNO\" + 1,\n"
         + "LOWER(\"t0\".\"DNAME\"),\n"
         + "UPPER(\"t0\".\"LOC\")";
     sql(sql6)
@@ -10040,7 +10040,7 @@ private void checkLiteral2(String expression, String expected) {
         + "ON \"t0\".\"EXPR$0\" = \"t1\".\"DEPTNO0\"\n"
         + "WHEN MATCHED THEN UPDATE SET \"DNAME\" = 'abc'\n"
         + "WHEN NOT MATCHED THEN INSERT (\"DEPTNO\", \"DNAME\", \"LOC\") "
-        + "VALUES CAST(\"t0\".\"EXPR$0\" + 1 AS TINYINT),\n"
+        + "VALUES \"t0\".\"EXPR$0\" + 1,\n"
         + "CAST(LOWER(\"t0\".\"EXPR$1\") AS VARCHAR(14) CHARACTER SET \"ISO-8859-1\"),\n"
         + "CAST(UPPER(\"t0\".\"EXPR$2\") AS VARCHAR(13) CHARACTER SET \"ISO-8859-1\")";
     sql(sql7)
@@ -10229,9 +10229,8 @@ private void checkLiteral2(String expression, String expected) {
     final String sql0 = "update \"foodmart\".\"product\" "
         + "set \"product_name\" = \"product_name\" || '_'\n"
         + "where \"product_id\" > 10";
-    final String expected0 = "UPDATE \"foodmart\".\"product\" SET \"product_name\" = CAST"
-        + "(\"product_name\" || '_' AS VARCHAR(60) CHARACTER SET \"ISO-8859-1\")\nWHERE "
-        + "\"product_id\" > 10";
+    final String expected0 = "UPDATE \"foodmart\".\"product\" SET \"product_name\" = "
+        + "\"product_name\" || '_'\nWHERE \"product_id\" > 10";
     sql(sql0).ok(expected0);
 
     final String sql1 = "update \"foodmart\".\"product\""
@@ -10247,8 +10246,8 @@ private void checkLiteral2(String expression, String expected) {
         + "   \"product_name\" = \"product_name\" || '_' \n"
         + "where \"product_id\" > 10";
     final String expected2 = "UPDATE \"foodmart\".\"product\" SET \"product_id\" = \"product_id\""
-        + " + CHAR_LENGTH(\"product_name\"), \"product_name\" = CAST(\"product_name\" || '_' AS "
-        + "VARCHAR(60) CHARACTER SET \"ISO-8859-1\")\nWHERE \"product_id\" > 10";
+        + " + CHAR_LENGTH(\"product_name\"), \"product_name\" = \"product_name\" || '_'"
+        + "\nWHERE \"product_id\" > 10";
     sql(sql2).ok(expected2);
 
     final String sql3 = "update \"foodmart\".\"product\"\n"

core/src/test/java/org/apache/calcite/test/JdbcAdapterTest.java

@@ -1456,21 +1456,21 @@ private LockWrapper exclusiveCleanDb(Connection c) throws SQLException {
         + "  JdbcTableModify(table=[[foodmart, expense_fact]], operation=[MERGE],"
         + " updateColumnList=[[amount]], flattened=[false])\n"
         + "    JdbcProject(STORE_ID=[$0], $f1=[666], $f2=[1997-01-01 00:00:00], $f3=[666],"
-        + " $f4=['666':VARCHAR(30)], $f5=[666], AMOUNT=[CAST($1):DECIMAL(10, 4) NOT NULL],"
+        + " $f4=['666':VARCHAR(30)], $f5=[666], AMOUNT=[$1],"
         + " store_id=[$2],"
         + " account_id=[$3], exp_date=[$4], time_id=[$5], category_id=[$6], currency_id=[$7],"
-        + " amount=[$8], AMOUNT0=[CAST($1):DECIMAL(10, 4) NOT NULL])\n"
+        + " amount=[$8], AMOUNT0=[$1])\n"
         + "      JdbcJoin(condition=[=($2, $0)], joinType=[left])\n"
         + "        JdbcValues(tuples=[[{ 666, 42 }]])\n"
         + "        JdbcTableScan(table=[[foodmart, expense_fact]])\n";
     final String jdbcSql = "MERGE INTO \"foodmart\".\"expense_fact\"\n"
         + "USING (VALUES (666, 42)) AS \"t\" (\"STORE_ID\", \"AMOUNT\")\n"
         + "ON \"t\".\"STORE_ID\" = \"expense_fact\".\"store_id\"\n"
-        + "WHEN MATCHED THEN UPDATE SET \"amount\" = CAST(\"t\".\"AMOUNT\" AS DECIMAL(10, 4))\n"
+        + "WHEN MATCHED THEN UPDATE SET \"amount\" = \"t\".\"AMOUNT\"\n"
         + "WHEN NOT MATCHED THEN INSERT (\"store_id\", \"account_id\", \"exp_date\", \"time_id\", "
         + "\"category_id\", \"currency_id\", \"amount\") VALUES \"t\".\"STORE_ID\",\n"
         + "666,\nTIMESTAMP '1997-01-01 00:00:00',\n666,\n'666',\n666,\n"
-        + "CAST(\"t\".\"AMOUNT\" AS DECIMAL(10, 4))";
+        + "\"t\".\"AMOUNT\"";
     final AssertThat that =
         CalciteAssert.model(FoodmartSchema.FOODMART_MODEL)
             .enable(CalciteAssert.DB == DatabaseInstance.HSQLDB);

core/src/test/java/org/apache/calcite/test/JdbcTest.java

@@ -390,7 +390,7 @@ static void forEachExpand(Runnable r) {
               + "expr#7=[null:JavaType(class java.lang.Integer)], "
               + "empid=[$t3], deptno=[$t4], name=[$t5], salary=[$t6], "
               + "commission=[$t7])\n"
-              + "    EnumerableValues(tuples=[[{ 'Fred', 56, 123.4000015258789E0 }]])\n";
+              + "    EnumerableValues(tuples=[[{ 'Fred', 56, 123.4 }]])\n";
           assertThat(resultSet.getString(1), isLinux(expected));
 
           // With named columns

core/src/test/java/org/apache/calcite/test/RelOptRulesTest.java

@@ -5972,7 +5972,7 @@ private void checkEmptyJoin(RelOptFixture f) {
   @Test void testReduceCastsNullable() {
     HepProgram program = new HepProgramBuilder()
 
-        // Simulate the way INSERT will insert casts to the target types
+        // Simulate the way INSERT can insert casts to the target types.
         .addRuleInstance(
             CoerceInputsRule.Config.DEFAULT
                 .withCoerceNames(false)

core/src/test/java/org/apache/calcite/test/TypeCoercionConverterTest.java

@@ -236,4 +236,36 @@ public static void checkActualAndReferenceFiles() {
     String sql = "select CAST(null AS INTEGER) union select '10'";
     sql(sql).ok();
   }
+
+  /** Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-7607">[CALCITE-7607]
+   * Avoid implicit narrowing casts in DML assignment coercion</a>. */
+  @Test void testInsertVarcharNarrowingKeepsSourceType() {
+    final String sql = "insert into t1 select "
+        + "CAST('AVeryLongLongStringValue' AS VARCHAR(64)), "
+        + "t2_smallint, t2_int, t2_bigint,\n"
+        + "t2_real, t2_double, t2_decimal, t2_timestamp, "
+        + "t2_date, t2_binary, t2_boolean from t2";
+    sql(sql).ok();
+  }
+
+  /** Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-7607">[CALCITE-7607]
+   * Avoid implicit narrowing casts in DML assignment coercion</a>. */
+  @Test void testUpdateVarcharNarrowingKeepsSourceType() {
+    final String sql = "update t1 set t1_varchar20 = "
+        + "CAST('AVeryLongLongStringValue' AS VARCHAR(64))";
+    sql(sql).ok();
+  }
+
+  /** Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-7607">[CALCITE-7607]
+   * Avoid implicit narrowing casts in DML assignment coercion</a>. */
+  @Test void testMergeVarcharNarrowingKeepsSourceType() {
+    final String sql = "merge into t1\n"
+        + "using t2 on t1.t1_smallint = t2.t2_smallint\n"
+        + "when matched then update set t1_varchar20 = "
+        + "CAST('AVeryLongLongStringValue' AS VARCHAR(64))";
+    sql(sql).ok();
+  }
 }

core/src/test/resources/org/apache/calcite/test/RelOptRulesTest.xml

@@ -16240,14 +16240,14 @@ select empno, cast(job as varchar(128)) from sales.empnullables]]>
     <Resource name="planBefore">
       <![CDATA[
 LogicalTableModify(table=[[CATALOG, SALES, DEPT]], operation=[INSERT], flattened=[false])
-  LogicalProject(DEPTNO=[$0], NAME=[$2])
+  LogicalProject(DEPTNO=[$0], NAME=[CAST($2):VARCHAR(128)])
     LogicalTableScan(table=[[CATALOG, SALES, EMPNULLABLES]])
 ]]>
     </Resource>
     <Resource name="planAfter">
       <![CDATA[
 LogicalTableModify(table=[[CATALOG, SALES, DEPT]], operation=[INSERT], flattened=[false])
-  LogicalCalc(expr#0..8=[{inputs}], expr#9=[CAST($t2):VARCHAR(10) NOT NULL], DEPTNO=[$t0], NAME=[$t9])
+  LogicalCalc(expr#0..8=[{inputs}], expr#9=[CAST($t2):VARCHAR(128)], DEPTNO=[$t0], NAME=[$t9])
     LogicalTableScan(table=[[CATALOG, SALES, EMPNULLABLES]])
 ]]>
     </Resource>

core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml

@@ -5517,7 +5517,7 @@ values(t.empno, t.ename, 10, t.sal * .15)]]>
     <Resource name="plan">
       <![CDATA[
 LogicalTableModify(table=[[CATALOG, SALES, EMPNULLABLES]], operation=[MERGE], updateColumnList=[[ENAME, DEPTNO, SAL]], flattened=[true])
-  LogicalProject(EMPNO=[$0], ENAME=[$1], $f2=[null:VARCHAR(10)], $f3=[null:INTEGER], $f4=[null:TIMESTAMP(0)], $f5=[CAST(*($5, 0.15:DECIMAL(2, 2))):INTEGER NOT NULL], $f6=[null:INTEGER], $f7=[10], $f8=[null:BOOLEAN], EMPNO0=[$9], ENAME0=[$10], JOB0=[$11], MGR0=[$12], HIREDATE0=[$13], SAL0=[$14], COMM0=[$15], DEPTNO0=[$16], SLACKER0=[$17], ENAME1=[$1], DEPTNO=[$7], $f20=[CAST(*($5, 0.1:DECIMAL(1, 1))):INTEGER NOT NULL])
+  LogicalProject(EMPNO=[$0], ENAME=[$1], $f2=[null:VARCHAR(10)], $f3=[null:INTEGER], $f4=[null:TIMESTAMP(0)], $f5=[*($5, 0.15:DECIMAL(2, 2))], $f6=[null:INTEGER], $f7=[10], $f8=[null:BOOLEAN], EMPNO0=[$9], ENAME0=[$10], JOB0=[$11], MGR0=[$12], HIREDATE0=[$13], SAL0=[$14], COMM0=[$15], DEPTNO0=[$16], SLACKER0=[$17], ENAME1=[$1], DEPTNO=[$7], $f20=[*($5, 0.1:DECIMAL(1, 1))])
     LogicalJoin(condition=[=($9, $0)], joinType=[left])
       LogicalProject(EMPNO=[$0], ENAME=[$1], JOB=[$2], MGR=[$3], HIREDATE=[$4], SAL=[$5], COMM=[$6], DEPTNO=[$7], SLACKER=[$8])
         LogicalFilter(condition=[IS NULL($7)])
@@ -7166,7 +7166,7 @@ LogicalTableModify(table=[[CATALOG, SALES, DEPT]], operation=[INSERT], flattened
   LogicalAggregate(group=[{0, 1}])
     LogicalProject(EMPNO=[$0], ENAME=[$1])
       LogicalFilter(condition=[$2])
-        LogicalProject(EMPNO=[$0], ENAME=[CAST($1):VARCHAR(10) NOT NULL], QualifyExpression=[=(RANK() OVER (PARTITION BY $1 ORDER BY $8 DESC), 1)])
+        LogicalProject(EMPNO=[$0], ENAME=[$1], QualifyExpression=[=(RANK() OVER (PARTITION BY $1 ORDER BY $8 DESC), 1)])
           LogicalFilter(condition=[>($7, 5)])
             LogicalTableScan(table=[[CATALOG, SALES, EMP]])
 ]]>