protected String generateAlterTableSql()

in catalogs/catalog-jdbc-postgresql/src/main/java/org/apache/gravitino/catalog/postgresql/operation/PostgreSqlTableOperations.java [309:384]
68 lines of code
18 McCabe index (conditional complexity)

  protected String generateAlterTableSql(
      String schemaName, String tableName, TableChange... changes) {
    // Not all operations require the original table information, so lazy loading is used here
    JdbcTable lazyLoadTable = null;
    List<String> alterSql = new ArrayList<>();
    for (TableChange change : changes) {
      if (change instanceof TableChange.UpdateComment) {
        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        alterSql.add(updateCommentDefinition((TableChange.UpdateComment) change, lazyLoadTable));
      } else if (change instanceof TableChange.SetProperty) {
        throw new IllegalArgumentException("Set property is not supported yet");
      } else if (change instanceof TableChange.RemoveProperty) {
        // PostgreSQL does not support deleting table attributes, it can be replaced by Set Property
        throw new IllegalArgumentException("Remove property is not supported yet");
      } else if (change instanceof TableChange.AddColumn) {
        TableChange.AddColumn addColumn = (TableChange.AddColumn) change;
        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        alterSql.addAll(addColumnFieldDefinition(addColumn, lazyLoadTable));
      } else if (change instanceof TableChange.RenameColumn) {
        TableChange.RenameColumn renameColumn = (TableChange.RenameColumn) change;
        alterSql.add(renameColumnFieldDefinition(renameColumn, tableName));
      } else if (change instanceof TableChange.UpdateColumnDefaultValue) {
        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        TableChange.UpdateColumnDefaultValue updateColumnDefaultValue =
            (TableChange.UpdateColumnDefaultValue) change;
        alterSql.add(
            updateColumnDefaultValueFieldDefinition(updateColumnDefaultValue, lazyLoadTable));
      } else if (change instanceof TableChange.UpdateColumnType) {
        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        TableChange.UpdateColumnType updateColumnType = (TableChange.UpdateColumnType) change;
        alterSql.add(updateColumnTypeFieldDefinition(updateColumnType, lazyLoadTable));
      } else if (change instanceof TableChange.UpdateColumnComment) {
        alterSql.add(
            updateColumnCommentFieldDefinition(
                (TableChange.UpdateColumnComment) change, tableName));
      } else if (change instanceof TableChange.UpdateColumnPosition) {
        throw new IllegalArgumentException("PostgreSQL does not support column position.");
      } else if (change instanceof TableChange.DeleteColumn) {
        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        TableChange.DeleteColumn deleteColumn = (TableChange.DeleteColumn) change;
        String deleteColSql = deleteColumnFieldDefinition(deleteColumn, lazyLoadTable);
        if (StringUtils.isNotEmpty(deleteColSql)) {
          alterSql.add(deleteColSql);
        }
      } else if (change instanceof TableChange.UpdateColumnNullability) {
        TableChange.UpdateColumnNullability updateColumnNullability =
            (TableChange.UpdateColumnNullability) change;

        lazyLoadTable = getOrCreateTable(schemaName, tableName, lazyLoadTable);
        validateUpdateColumnNullable(updateColumnNullability, lazyLoadTable);

        alterSql.add(updateColumnNullabilityDefinition(updateColumnNullability, tableName));
      } else if (change instanceof TableChange.AddIndex) {
        alterSql.add(addIndexDefinition(tableName, (TableChange.AddIndex) change));
      } else if (change instanceof TableChange.DeleteIndex) {
        alterSql.add(deleteIndexDefinition(tableName, (TableChange.DeleteIndex) change));
      } else if (change instanceof TableChange.UpdateColumnAutoIncrement) {
        alterSql.add(
            updateColumnAutoIncrementDefinition(
                (TableChange.UpdateColumnAutoIncrement) change, tableName));
      } else {
        throw new IllegalArgumentException(
            "Unsupported table change type: " + change.getClass().getName());
      }
    }

    // If there is no change, return directly
    if (alterSql.isEmpty()) {
      return "";
    }

    // Return the generated SQL statement
    String result = String.join("\n", alterSql);
    LOG.info("Generated alter table:{}.{} sql: {}", schemaName, tableName, result);
    return result;
  }