Examples with SelectOperator org.apache.hadoop.hive.ql.exec.SelectOperator used on opensource projects

Example 31 with SelectOperator

use of org.apache.hadoop.hive.ql.exec.SelectOperator in project hive by apache.

the class ColumnStatsAutoGatherContext method genSelOpForAnalyze.

@SuppressWarnings("rawtypes")
private Operator genSelOpForAnalyze(String analyzeCommand, Context origCtx) throws IOException, ParseException, SemanticException {
    // 0. initialization
    Context ctx = new Context(conf);
    ctx.setExplainConfig(origCtx.getExplainConfig());
    ASTNode tree = ParseUtils.parse(analyzeCommand, ctx);
    // 1. get the ColumnStatsSemanticAnalyzer
    QueryState queryState = new QueryState.Builder().withHiveConf(conf).build();
    BaseSemanticAnalyzer baseSem = SemanticAnalyzerFactory.get(queryState, tree);
    ColumnStatsSemanticAnalyzer colSem = (ColumnStatsSemanticAnalyzer) baseSem;
    // 2. get the rewritten AST
    ASTNode ast = colSem.rewriteAST(tree, this);
    baseSem = SemanticAnalyzerFactory.get(queryState, ast);
    SemanticAnalyzer sem = (SemanticAnalyzer) baseSem;
    QB qb = new QB(null, null, false);
    ASTNode child = ast;
    ParseContext subPCtx = ((SemanticAnalyzer) sem).getParseContext();
    subPCtx.setContext(ctx);
    ((SemanticAnalyzer) sem).initParseCtx(subPCtx);
    sem.doPhase1(child, qb, sem.initPhase1Ctx(), null);
    // This will trigger new calls to metastore to collect metadata
    // TODO: cache the information from the metastore
    sem.getMetaData(qb);
    Operator<?> operator = sem.genPlan(qb);
    // 3. populate the load file work so that ColumnStatsTask can work
    loadFileWork.addAll(sem.getLoadFileWork());
    // 4. because there is only one TS for analyze statement, we can get it.
    if (sem.topOps.values().size() != 1) {
        throw new SemanticException("ColumnStatsAutoGatherContext is expecting exactly one TS, but finds " + sem.topOps.values().size());
    }
    operator = sem.topOps.values().iterator().next();
    // 5. get the first SEL after TS
    while (!(operator instanceof SelectOperator)) {
        operator = operator.getChildOperators().get(0);
    }
    return operator;
}