use of org.apache.druid.segment.column.ColumnType in project druid by druid-io.
the class ExpressionSelectors method makeExprEvalSelector.
public static ColumnValueSelector<ExprEval> makeExprEvalSelector(ColumnSelectorFactory columnSelectorFactory, ExpressionPlan plan) {
if (plan.is(ExpressionPlan.Trait.SINGLE_INPUT_SCALAR)) {
final String column = plan.getSingleInputName();
final ColumnType inputType = plan.getSingleInputType();
if (inputType.is(ValueType.LONG)) {
return new SingleLongInputCachingExpressionColumnValueSelector(columnSelectorFactory.makeColumnValueSelector(column), plan.getExpression(), // __time doesn't need an LRU cache since it is sorted.
!ColumnHolder.TIME_COLUMN_NAME.equals(column));
} else if (inputType.is(ValueType.STRING)) {
return new SingleStringInputCachingExpressionColumnValueSelector(columnSelectorFactory.makeDimensionSelector(new DefaultDimensionSpec(column, column, ColumnType.STRING)), plan.getExpression());
}
}
final Expr.ObjectBinding bindings = createBindings(columnSelectorFactory, plan);
// Optimization for constant expressions
if (bindings.equals(InputBindings.nilBindings())) {
return new ConstantExprEvalSelector(plan.getExpression().eval(bindings));
}
// per row basis
if (plan.any(ExpressionPlan.Trait.UNKNOWN_INPUTS, ExpressionPlan.Trait.INCOMPLETE_INPUTS)) {
return new RowBasedExpressionColumnValueSelector(plan, bindings);
}
// generic expression value selector for fully known input types
return new ExpressionColumnValueSelector(plan.getAppliedExpression(), bindings);
}
use of org.apache.druid.segment.column.ColumnType in project druid by druid-io.
the class ExpressionPlanner method plan.
/**
* Druid tries to be chill to expressions to make up for not having a well defined table schema across segments. This
* method performs some analysis to determine what sort of selectors can be constructed on top of an expression,
* whether or not the expression will need implicitly mapped across multi-valued inputs, if the expression produces
* multi-valued outputs, is vectorizable, and everything else interesting when making a selector.
*
* Results are stored in a {@link ExpressionPlan}, which can be examined to do whatever is necessary to make things
* function properly.
*/
public static ExpressionPlan plan(ColumnInspector inspector, Expr expression) {
final Expr.BindingAnalysis analysis = expression.analyzeInputs();
Parser.validateExpr(expression, analysis);
EnumSet<ExpressionPlan.Trait> traits = EnumSet.noneOf(ExpressionPlan.Trait.class);
Set<String> noCapabilities = new HashSet<>();
Set<String> maybeMultiValued = new HashSet<>();
List<String> needsApplied = ImmutableList.of();
ColumnType singleInputType = null;
ExpressionType outputType = null;
final Set<String> columns = analysis.getRequiredBindings();
// check and set traits which allow optimized selectors to be created
if (columns.isEmpty()) {
traits.add(ExpressionPlan.Trait.CONSTANT);
} else if (expression.isIdentifier()) {
traits.add(ExpressionPlan.Trait.IDENTIFIER);
} else if (columns.size() == 1) {
final String column = Iterables.getOnlyElement(columns);
final ColumnCapabilities capabilities = inspector.getColumnCapabilities(column);
// (i.e. the expression is not treating its input as an array and not wanting to output an array)
if (capabilities != null && !analysis.hasInputArrays() && !analysis.isOutputArray()) {
boolean isSingleInputMappable = false;
boolean isSingleInputScalar = capabilities.hasMultipleValues().isFalse();
if (capabilities.is(ValueType.STRING)) {
isSingleInputScalar &= capabilities.isDictionaryEncoded().isTrue();
isSingleInputMappable = capabilities.isDictionaryEncoded().isTrue() && !capabilities.hasMultipleValues().isUnknown();
}
// if satisfied, set single input output type and flags
if (isSingleInputScalar || isSingleInputMappable) {
singleInputType = capabilities.toColumnType();
if (isSingleInputScalar) {
traits.add(ExpressionPlan.Trait.SINGLE_INPUT_SCALAR);
}
if (isSingleInputMappable) {
traits.add(ExpressionPlan.Trait.SINGLE_INPUT_MAPPABLE);
}
}
}
}
// automatic transformation to map across multi-valued inputs (or row by row detection in the worst case)
if (ExpressionPlan.none(traits, ExpressionPlan.Trait.SINGLE_INPUT_SCALAR, ExpressionPlan.Trait.CONSTANT, ExpressionPlan.Trait.IDENTIFIER)) {
final Set<String> definitelyMultiValued = new HashSet<>();
final Set<String> definitelyArray = new HashSet<>();
for (String column : analysis.getRequiredBindings()) {
final ColumnCapabilities capabilities = inspector.getColumnCapabilities(column);
if (capabilities != null) {
if (capabilities.isArray()) {
definitelyArray.add(column);
} else if (capabilities.is(ValueType.STRING) && capabilities.hasMultipleValues().isTrue()) {
definitelyMultiValued.add(column);
} else if (capabilities.is(ValueType.STRING) && capabilities.hasMultipleValues().isMaybeTrue() && !analysis.getArrayBindings().contains(column)) {
maybeMultiValued.add(column);
}
} else {
noCapabilities.add(column);
}
}
// find any inputs which will need implicitly mapped across multi-valued rows
needsApplied = columns.stream().filter(c -> !definitelyArray.contains(c) && definitelyMultiValued.contains(c) && !analysis.getArrayBindings().contains(c)).collect(Collectors.toList());
// if any multi-value inputs, set flag for non-scalar inputs
if (analysis.hasInputArrays()) {
traits.add(ExpressionPlan.Trait.NON_SCALAR_INPUTS);
}
if (!noCapabilities.isEmpty()) {
traits.add(ExpressionPlan.Trait.UNKNOWN_INPUTS);
}
if (!maybeMultiValued.isEmpty()) {
traits.add(ExpressionPlan.Trait.INCOMPLETE_INPUTS);
}
// if expression needs transformed, lets do it
if (!needsApplied.isEmpty()) {
traits.add(ExpressionPlan.Trait.NEEDS_APPLIED);
}
}
// only set output type if we are pretty confident about input types
final boolean shouldComputeOutput = ExpressionPlan.none(traits, ExpressionPlan.Trait.UNKNOWN_INPUTS, ExpressionPlan.Trait.INCOMPLETE_INPUTS);
if (shouldComputeOutput) {
outputType = expression.getOutputType(inspector);
}
// if analysis predicts output, or inferred output type, is array, output will be arrays
if (analysis.isOutputArray() || (outputType != null && outputType.isArray())) {
traits.add(ExpressionPlan.Trait.NON_SCALAR_OUTPUT);
// single input mappable may not produce array output explicitly, only through implicit mapping
traits.remove(ExpressionPlan.Trait.SINGLE_INPUT_SCALAR);
traits.remove(ExpressionPlan.Trait.SINGLE_INPUT_MAPPABLE);
}
// vectorized expressions do not support incomplete, multi-valued inputs or outputs, or implicit mapping
// they also do not support unknown inputs, but they also do not currently have to deal with them, as missing
// capabilites is indicative of a non-existent column instead of an unknown schema. If this ever changes,
// this check should also change
boolean supportsVector = ExpressionPlan.none(traits, ExpressionPlan.Trait.INCOMPLETE_INPUTS, ExpressionPlan.Trait.NEEDS_APPLIED, ExpressionPlan.Trait.NON_SCALAR_INPUTS, ExpressionPlan.Trait.NON_SCALAR_OUTPUT);
if (supportsVector && expression.canVectorize(inspector)) {
// make sure to compute the output type for a vector expression though, because we might have skipped it earlier
// due to unknown inputs, but that's ok here since it just means it doesnt exist
outputType = expression.getOutputType(inspector);
traits.add(ExpressionPlan.Trait.VECTORIZABLE);
}
return new ExpressionPlan(inspector, expression, analysis, traits, outputType, singleInputType, Sets.union(noCapabilities, maybeMultiValued), needsApplied);
}
use of org.apache.druid.segment.column.ColumnType in project druid by druid-io.
the class FinalizingFieldAccessPostAggregator method decorate.
@Override
public FinalizingFieldAccessPostAggregator decorate(final Map<String, AggregatorFactory> aggregators) {
final Comparator<Object> theComparator;
final Function<Object, Object> theFinalizer;
final ColumnType finalizedType;
if (aggregators != null && aggregators.containsKey(fieldName)) {
// noinspection unchecked
theComparator = aggregators.get(fieldName).getComparator();
theFinalizer = aggregators.get(fieldName)::finalizeComputation;
finalizedType = aggregators.get(fieldName).getResultType();
} else {
// noinspection unchecked
theComparator = (Comparator) Comparators.naturalNullsFirst();
theFinalizer = Function.identity();
finalizedType = null;
}
return new FinalizingFieldAccessPostAggregator(name, fieldName, finalizedType, theComparator, theFinalizer);
}
use of org.apache.druid.segment.column.ColumnType in project druid by druid-io.
the class Projection method postAggregatorComplexDirectColumnIsOk.
/**
* Returns true if a post-aggregation "expression" can be realized as a direct field access. This is true if it's
* a direct column access that doesn't require an implicit cast.
*
* @param aggregateRowSignature signature of the aggregation
* @param expression post-aggregation expression
* @param rexNode RexNode for the post-aggregation expression
*
* @return yes or no
*/
private static boolean postAggregatorComplexDirectColumnIsOk(final RowSignature aggregateRowSignature, final DruidExpression expression, final RexNode rexNode) {
if (!expression.isDirectColumnAccess()) {
return false;
}
// Check if a cast is necessary.
final ColumnType toValueType = aggregateRowSignature.getColumnType(expression.getDirectColumn()).orElseThrow(() -> new ISE("Encountered null type for column[%s]", expression.getDirectColumn()));
final ColumnType fromValueType = Calcites.getColumnTypeForRelDataType(rexNode.getType());
return toValueType.is(ValueType.COMPLEX) && toValueType.equals(fromValueType);
}
use of org.apache.druid.segment.column.ColumnType in project druid by druid-io.
the class SystemSchemaTest method verifyTypes.
private static void verifyTypes(final List<Object[]> rows, final RowSignature signature) {
final RelDataType rowType = RowSignatures.toRelDataType(signature, new JavaTypeFactoryImpl());
for (Object[] row : rows) {
Assert.assertEquals(row.length, signature.size());
for (int i = 0; i < row.length; i++) {
final Class<?> expectedClass;
final ColumnType columnType = signature.getColumnType(i).orElseThrow(() -> new ISE("Encountered null column type"));
final boolean nullable = rowType.getFieldList().get(i).getType().isNullable();
switch(columnType.getType()) {
case LONG:
expectedClass = Long.class;
break;
case FLOAT:
expectedClass = Float.class;
break;
case DOUBLE:
expectedClass = Double.class;
break;
case STRING:
if (signature.getColumnName(i).equals("segment_id")) {
expectedClass = SegmentId.class;
} else {
expectedClass = String.class;
}
break;
default:
throw new IAE("Don't know what class to expect for valueType[%s]", columnType);
}
if (nullable) {
Assert.assertTrue(StringUtils.format("Column[%s] is a [%s] or null (was %s)", signature.getColumnName(i), expectedClass.getName(), row[i] == null ? null : row[i].getClass().getName()), row[i] == null || expectedClass.isAssignableFrom(row[i].getClass()));
} else {
Assert.assertTrue(StringUtils.format("Column[%s] is a [%s] (was %s)", signature.getColumnName(i), expectedClass.getName(), row[i] == null ? null : row[i].getClass().getName()), row[i] != null && expectedClass.isAssignableFrom(row[i].getClass()));
}
}
}
}
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