Examples with Column io.prestosql.client.Column used on opensource projects

Example 11 with Column

use of io.prestosql.client.Column in project hetu-core by openlookeng.

the class ColumnService method queryColumns.

private List<Column> queryColumns(String fqnTableName, String user) {
    String statement = format("SHOW COLUMNS FROM %s", fqnTableName);
    QueryRunner queryRunner = queryRunnerFactory.create(QueryEditorUIModule.UI_QUERY_SOURCE, user);
    QueryClient queryClient = new QueryClient(queryRunner, Duration.standardSeconds(60), statement);
    final ImmutableList.Builder<Column> cache = ImmutableList.builder();
    try {
        queryClient.executeWith(new Function<StatementClient, Void>() {

            @Nullable
            @Override
            public Void apply(StatementClient client) {
                QueryData results = client.currentData();
                if (results.getData() != null) {
                    for (List<Object> row : results.getData()) {
                        TypeSignature typeSignature = TypeSignature.parseTypeSignature((String) row.get(1));
                        Column column = new Column((String) row.get(0), (String) row.get(1), Query.toClientTypeSignature(typeSignature));
                        cache.add(column);
                    }
                }
                return null;
            }
        });
    } catch (QueryClient.QueryTimeOutException e) {
        log.error("Caught timeout loading columns", e);
    }
    return cache.build();
}