Examples with HiveJdbcImplementor org.apache.hadoop.hive.ql.optimizer.calcite.rules.jdbc.HiveJdbcImplementor used on opensource projects

Example 1 with HiveJdbcImplementor

use of org.apache.hadoop.hive.ql.optimizer.calcite.rules.jdbc.HiveJdbcImplementor in project hive by apache.

the class HiveJdbcConverter method generateSql.

public String generateSql() {
    SqlDialect dialect = getJdbcDialect();
    final HiveJdbcImplementor jdbcImplementor = new HiveJdbcImplementor(dialect, (JavaTypeFactory) getCluster().getTypeFactory());
    Project topProject;
    if (getInput() instanceof Project) {
        topProject = (Project) getInput();
    } else {
        // If it is not a project operator, we add it on top of the input
        // to force generating the column names instead of * while
        // translating to SQL
        RelNode nodeToTranslate = getInput();
        RexBuilder builder = getCluster().getRexBuilder();
        List<RexNode> projects = new ArrayList<>(nodeToTranslate.getRowType().getFieldList().size());
        for (int i = 0; i < nodeToTranslate.getRowType().getFieldCount(); i++) {
            projects.add(builder.makeInputRef(nodeToTranslate, i));
        }
        topProject = new JdbcProject(nodeToTranslate.getCluster(), nodeToTranslate.getTraitSet(), nodeToTranslate, projects, nodeToTranslate.getRowType());
    }
    final HiveJdbcImplementor.Result result = jdbcImplementor.visitRoot(topProject);
    return result.asStatement().toSqlString(dialect).getSql();
}