Correct behavior of Connection.createArrayOf

Author: zhicwu

clickhouse-client/src/main/java/com/clickhouse/client/ClickHouseColumn.java

@@ -48,14 +48,16 @@ private static ClickHouseColumn update(ClickHouseColumn column) {
         column.precision = column.dataType.getMaxPrecision();
         switch (column.dataType) {
             case Array:
-                column.arrayLevel = 1;
-                column.arrayBaseColumn = column.nested.get(0);
-                while (column.arrayLevel < 255) {
-                    if (column.arrayBaseColumn.dataType == ClickHouseDataType.Array) {
-                        column.arrayLevel++;
-                        column.arrayBaseColumn = column.arrayBaseColumn.nested.get(0);
-                    } else {
-                        break;
+                if (!column.nested.isEmpty()) {
+                    column.arrayLevel = 1;
+                    column.arrayBaseColumn = column.nested.get(0);
+                    while (column.arrayLevel < 255) {
+                        if (column.arrayBaseColumn.dataType == ClickHouseDataType.Array) {
+                            column.arrayLevel++;
+                            column.arrayBaseColumn = column.arrayBaseColumn.nested.get(0);
+                        } else {
+                            break;
+                        }
                     }
                 }
                 break;
@@ -101,10 +103,14 @@ private static ClickHouseColumn update(ClickHouseColumn column) {
             case Decimal64:
             case Decimal128:
             case Decimal256:
-                column.scale = Integer.parseInt(column.parameters.get(0));
+                if (size > 0) {
+                    column.scale = Integer.parseInt(column.parameters.get(0));
+                }
                 break;
             case FixedString:
-                column.precision = Integer.parseInt(column.parameters.get(0));
+                if (size > 0) {
+                    column.precision = Integer.parseInt(column.parameters.get(0));
+                }
                 break;
             default:
                 break;
@@ -307,13 +313,14 @@ public static ClickHouseColumn of(String columnName, ClickHouseDataType dataType
 
     public static ClickHouseColumn of(String columnName, ClickHouseDataType dataType, boolean nullable,
             boolean lowCardinality, String... parameters) {
-        return new ClickHouseColumn(dataType, columnName, null, nullable, lowCardinality, Arrays.asList(parameters),
-                null);
+        return update(new ClickHouseColumn(dataType, columnName, null, nullable, lowCardinality,
+                Arrays.asList(parameters), null));
     }
 
     public static ClickHouseColumn of(String columnName, ClickHouseDataType dataType, boolean nullable,
             ClickHouseColumn... nestedColumns) {
-        return new ClickHouseColumn(dataType, columnName, null, nullable, false, null, Arrays.asList(nestedColumns));
+        return update(
+                new ClickHouseColumn(dataType, columnName, null, nullable, false, null, Arrays.asList(nestedColumns)));
     }
 
     public static ClickHouseColumn of(String columnName, String columnType) {

clickhouse-jdbc/src/main/java/com/clickhouse/jdbc/ClickHouseConnection.java

@@ -14,6 +14,7 @@
 
 import com.clickhouse.client.ClickHouseColumn;
 import com.clickhouse.client.ClickHouseConfig;
+import com.clickhouse.client.ClickHouseDataType;
 import com.clickhouse.client.ClickHouseValue;
 import com.clickhouse.client.ClickHouseValues;
 import com.clickhouse.client.ClickHouseVersion;
@@ -36,7 +37,8 @@ public interface ClickHouseConnection extends Connection {
     @Override
     default ClickHouseArray createArrayOf(String typeName, Object[] elements) throws SQLException {
         ClickHouseConfig config = getConfig();
-        ClickHouseColumn column = ClickHouseColumn.of("", typeName);
+        ClickHouseColumn column = ClickHouseColumn.of("", ClickHouseDataType.Array, false,
+                ClickHouseColumn.of("", typeName));
         ClickHouseValue v = ClickHouseValues.newValue(config, column).update(elements);
         ClickHouseResultSet rs = new ClickHouseResultSet("", "", createStatement(),
                 ClickHouseSimpleResponse.of(config, Collections.singletonList(column),

clickhouse-jdbc/src/test/java/com/clickhouse/jdbc/ClickHousePreparedStatementTest.java

@@ -882,6 +882,27 @@ public void testInsertStringAsArray() throws Exception {
             Assert.assertEquals(rs.getObject(3), new long[] { 3, 0, 1 });
             Assert.assertFalse(rs.next());
         }
+
+        try (ClickHouseConnection conn = newConnection(new Properties());
+                Statement s = conn.createStatement()) {
+            s.execute("drop table if exists test_string_array_insert; "
+                    + "create table test_string_array_insert(id UInt32, a Array(LowCardinality(String)), b Array(Nullable(String)))engine=Memory");
+
+            try (PreparedStatement stmt = conn.prepareStatement(
+                    "insert into test_string_array_insert(id, a, b) values (?,?,?)")) {
+                stmt.setString(1, "1");
+                stmt.setObject(2, new String[] { "1", "2", "3" });
+                stmt.setArray(3, conn.createArrayOf("String", new String[] { "3", null, "1" }));
+                Assert.assertEquals(stmt.executeUpdate(), 1);
+            }
+
+            ResultSet rs = s.executeQuery("select * from test_string_array_insert order by id");
+            Assert.assertTrue(rs.next());
+            Assert.assertEquals(rs.getInt(1), 1);
+            Assert.assertEquals(rs.getArray(2).getArray(), new String[] { "1", "2", "3" });
+            Assert.assertEquals(rs.getObject(3), new String[] { "3", null, "1" });
+            Assert.assertFalse(rs.next());
+        }
     }
 
     @Test(groups = "integration")