org.apache.drill.exec.record.metadata

Class AbstractColumnMetadata

java.lang.Object

org.apache.drill.exec.record.metadata.AbstractPropertied

org.apache.drill.exec.record.metadata.AbstractColumnMetadata

All Implemented Interfaces:

ColumnMetadata, Propertied

Direct Known Subclasses:

AbstractMapColumnMetadata, DynamicColumn, PrimitiveColumnMetadata, RepeatedListColumnMetadata, VariantColumnMetadata

public abstract class AbstractColumnMetadata
extends AbstractPropertied
implements ColumnMetadata

Abstract definition of column metadata. Allows applications to create specialized forms of a column metadata object by extending from this abstract class.

Note that, by design, primitive columns do not have a link to their tuple parent, or their index within that parent. This allows the same metadata to be shared between two views of a tuple, perhaps physical and projected views. This restriction does not apply to map columns, since maps (and the row itself) will, by definition, differ between the two views.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.drill.exec.record.metadata.ColumnMetadata

ColumnMetadata.StructureType

Field Summary

Fields

Modifier and Type	Field and Description
protected TypeProtos.DataMode	mode
protected String	name
protected int	precision
protected int	scale
protected TypeProtos.MinorType	type

Fields inherited from interface org.apache.drill.exec.record.metadata.ColumnMetadata

BLANK_AS_NULL, BLANK_AS_PROP, BLANK_AS_ZERO, DEFAULT_ARRAY_SIZE, DEFAULT_VALUE_PROP, EXCLUDE_FROM_WILDCARD, EXPECTED_CARDINALITY_PROP, EXPECTED_WIDTH_PROP, FORMAT_PROP, IMPLICIT_COL_TYPE, IMPLICIT_FILENAME, IMPLICIT_FILEPATH, IMPLICIT_FQN, IMPLICIT_PARTITION_PREFIX, IMPLICIT_SUFFIX

Fields inherited from interface org.apache.drill.exec.record.metadata.Propertied

DRILL_PROP_PREFIX

Constructor Summary

Constructors

Constructor and Description
AbstractColumnMetadata(AbstractColumnMetadata from)
AbstractColumnMetadata(MaterializedField schema)
AbstractColumnMetadata(String name, TypeProtos.MajorType majorType)
AbstractColumnMetadata(String name, TypeProtos.MinorType type, TypeProtos.DataMode mode)

Method Summary

Modifier and Type	Method and Description
protected void	appendContents(StringBuilder buf)
void	bind(TupleMetadata parentTuple)
ColumnMetadata	childSchema() Schema of inner dimension for MULTI_ARRAY columns.
String	columnString() Converts column metadata into string representation accepted by the table schema parser.
static AbstractColumnMetadata	createColumnMetadata(String name, String type, TypeProtos.DataMode mode, Map<String,String> properties)
DateTimeFormatter	dateTimeFormatter() Returns the formatter to use for date/time values.
Object	decodeDefaultValue() Returns the default value decoded into object form.
String	defaultValue() Returns the default value for this column in String literal representation.
int	dimensions()
boolean	equals(Object o)
boolean	equalsWithProperties(AbstractColumnMetadata other)
boolean	equalsWithProperties(Object o)
protected String	escapeSpecialSymbols(String value) If given value contains backticks (`) or backslashes (\), escapes them.
int	expectedElementCount() Returns the expected array cardinality for array columns, or 1 for non-array columns.
int	expectedWidth() Get the expected width for a column.
String	format()
boolean	isArray()
boolean	isDict()
boolean	isDynamic() Reports if the column is dynamic.
boolean	isEquivalent(ColumnMetadata o) Report whether one column is equivalent to another.
boolean	isMap()
boolean	isMultiList() Determine if the schema represents a column with a LIST type with UNION elements.
boolean	isNullable()
boolean	isVariableWidth()
boolean	isVariant()
TypeProtos.MajorType	majorType()
TypeProtos.DataMode	mode()
String	name()
int	precision() Returns precision for current column.
Map<String,String>	properties()
int	scale() Returns scale for current column.
void	setDefaultValue(String value) Sets the default value property using the string-encoded form of the value.
void	setExpectedElementCount(int childCount) For an array column, specify the expected average array cardinality.
void	setExpectedWidth(int width) For variable-width columns, specify the expected column width to be used when allocating a new vector.
void	setFormat(String value)
String	toString()
TupleMetadata	tupleSchema() Schema for TUPLE columns.
TypeProtos.MinorType	type()
abstract String	typeString() Converts type metadata into string representation accepted by the table schema parser.
Object	valueFromString(String value)
String	valueToString(Object value)
VariantMetadata	variantSchema() Schema for VARIANT columns.

Methods inherited from class org.apache.drill.exec.record.metadata.AbstractPropertied

booleanProperty, booleanProperty, hashCode, hasProperties, intProperty, intProperty, property, property, removeProperty, setBooleanProperty, setIntProperty, setProperties, setProperty

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.drill.exec.record.metadata.ColumnMetadata

cloneEmpty, copy, emptySchema, schema, structureType

Methods inherited from interface org.apache.drill.exec.record.metadata.Propertied

booleanProperty, booleanProperty, hasProperties, intProperty, intProperty, pluginPrefix, property, property, removeProperty, setBooleanProperty, setIntProperty, setProperties, setProperty

Field Detail

name

protected final String name

type

protected final TypeProtos.MinorType type

mode

protected final TypeProtos.DataMode mode

precision

protected final int precision

scale

protected final int scale

Constructor Detail

AbstractColumnMetadata

public AbstractColumnMetadata(MaterializedField schema)

AbstractColumnMetadata

public AbstractColumnMetadata(String name,
                              TypeProtos.MajorType majorType)

AbstractColumnMetadata

public AbstractColumnMetadata(String name,
                              TypeProtos.MinorType type,
                              TypeProtos.DataMode mode)

AbstractColumnMetadata

public AbstractColumnMetadata(AbstractColumnMetadata from)

Method Detail

createColumnMetadata

public static AbstractColumnMetadata createColumnMetadata(String name,
                                                          String type,
                                                          TypeProtos.DataMode mode,
                                                          Map<String,String> properties)
                                                   throws IOException

Throws:

IOException

bind

public void bind(TupleMetadata parentTuple)

Specified by:

bind in interface ColumnMetadata

name

public String name()

Specified by:

name in interface ColumnMetadata

type

public TypeProtos.MinorType type()

Specified by:

type in interface ColumnMetadata

majorType

public TypeProtos.MajorType majorType()

Specified by:

majorType in interface ColumnMetadata

mode

public TypeProtos.DataMode mode()

Specified by:

mode in interface ColumnMetadata

isNullable

public boolean isNullable()

Specified by:

isNullable in interface ColumnMetadata

isArray

public boolean isArray()

Specified by:

isArray in interface ColumnMetadata

dimensions

public int dimensions()

Specified by:

dimensions in interface ColumnMetadata

isMap

public boolean isMap()

Specified by:

isMap in interface ColumnMetadata

isVariant

public boolean isVariant()

Specified by:

isVariant in interface ColumnMetadata

isMultiList

public boolean isMultiList()

Description copied from interface: ColumnMetadata

Determine if the schema represents a column with a LIST type with UNION elements. (Lists can be of a single type (with nullable elements) or can be of unions.)

Specified by:

isMultiList in interface ColumnMetadata

Returns:

true if the column is of type LIST of UNIONs

isDict

public boolean isDict()

Specified by:

isDict in interface ColumnMetadata

isDynamic

public boolean isDynamic()

Description copied from interface: ColumnMetadata

Reports if the column is dynamic. A dynamic column is one with a "type to be named later." It is valid for describing a dynamic schema, but not for creating vectors; to create a vector the column must be resolved to a concrete type. The context should make it clear if any columns can be dynamic.

Specified by:

isDynamic in interface ColumnMetadata

Returns:

true if the column does not yet have a concrete type, false if the column type is concrete

tupleSchema

public TupleMetadata tupleSchema()

Description copied from interface: ColumnMetadata

Schema for TUPLE columns.

Specified by:

tupleSchema in interface ColumnMetadata

Returns:

the tuple schema

variantSchema

public VariantMetadata variantSchema()

Description copied from interface: ColumnMetadata

Schema for VARIANT columns.

Specified by:

variantSchema in interface ColumnMetadata

Returns:

the variant schema

childSchema

public ColumnMetadata childSchema()

Description copied from interface: ColumnMetadata

Schema of inner dimension for MULTI_ARRAY columns. If an array is 3D, the outer column represents all 3 dimensions. outer.childSchema() gives another MULTI_ARRAY for the inner 2D array. outer.childSchema().childSchema() gives a column of some other type (but repeated) for the 1D array.

Sorry for the mess, but it is how the code works and we are not in a position to revisit data type fundamentals.

Specified by:

childSchema in interface ColumnMetadata

Returns:

the description of the (n-1) st dimension.

isVariableWidth

public boolean isVariableWidth()

Specified by:

isVariableWidth in interface ColumnMetadata

isEquivalent

public boolean isEquivalent(ColumnMetadata o)

Description copied from interface: ColumnMetadata

Report whether one column is equivalent to another. Columns are equivalent if they have the same name, type and structure (ignoring internal structure such as properties.)

Specified by:

isEquivalent in interface ColumnMetadata

equalsWithProperties

public boolean equalsWithProperties(AbstractColumnMetadata other)

expectedWidth

public int expectedWidth()

Description copied from interface: ColumnMetadata

Get the expected width for a column. This is the actual width for fixed- width columns, the specified width (defaulting to 50) for variable-width columns.

Specified by:

expectedWidth in interface ColumnMetadata

Returns:

the expected column width of the each data value. Does not include "overhead" space such as for the null-value vector or offset vector

setExpectedWidth

public void setExpectedWidth(int width)

Description copied from interface: ColumnMetadata

For variable-width columns, specify the expected column width to be used when allocating a new vector. Does nothing for fixed-width columns.

Specified by:

setExpectedWidth in interface ColumnMetadata

Parameters:

width - the expected column width

precision

public int precision()

Returns precision for current column. For the case when precision is not set or column type does not support precision, negative value will be returned.

Specified by:

precision in interface ColumnMetadata

Returns:

precision for current column

scale

public int scale()

Returns scale for current column. For the case when scale is not set or column type does not support scale, negative value will be returned.

Specified by:

scale in interface ColumnMetadata

Returns:

scale for current column

setExpectedElementCount

public void setExpectedElementCount(int childCount)

Description copied from interface: ColumnMetadata

For an array column, specify the expected average array cardinality. Ignored for non-array columns. Used when allocating new vectors.

Specified by:

setExpectedElementCount in interface ColumnMetadata

Parameters:

childCount - the expected average array cardinality. Defaults to 1 for non-array columns, 10 for array columns

expectedElementCount

public int expectedElementCount()

Description copied from interface: ColumnMetadata

Returns the expected array cardinality for array columns, or 1 for non-array columns.

Specified by:

expectedElementCount in interface ColumnMetadata

Returns:

the expected value cardinality per value (per-row for top-level columns, per array element for arrays within lists)

setFormat

public void setFormat(String value)

Specified by:

setFormat in interface ColumnMetadata

format

public String format()

Specified by:

format in interface ColumnMetadata

dateTimeFormatter

public DateTimeFormatter dateTimeFormatter()

Description copied from interface: ColumnMetadata

Returns the formatter to use for date/time values. Only valid for date/time columns.

Specified by:

dateTimeFormatter in interface ColumnMetadata

Returns:

setDefaultValue

public void setDefaultValue(String value)

Description copied from interface: ColumnMetadata

Sets the default value property using the string-encoded form of the value. The default value is used for filling a vector when no real data is available.

Specified by:

setDefaultValue in interface ColumnMetadata

Parameters:

value - the default value in String representation

defaultValue

public String defaultValue()

Description copied from interface: ColumnMetadata

Returns the default value for this column in String literal representation.

Specified by:

defaultValue in interface ColumnMetadata

Returns:

the default value in String literal representation, or null if no default value has been set

decodeDefaultValue

public Object decodeDefaultValue()

Description copied from interface: ColumnMetadata

Returns the default value decoded into object form. This is the same as:

decodeValue(defaultValue());
 

Specified by:

decodeDefaultValue in interface ColumnMetadata

Returns:

the default value decode as an object that can be passed to the ColumnWriter#setObject() method.

valueFromString

public Object valueFromString(String value)

Specified by:

valueFromString in interface ColumnMetadata

valueToString

public String valueToString(Object value)

Specified by:

valueToString in interface ColumnMetadata

properties

public Map<String,String> properties()

Specified by:

properties in interface Propertied

Overrides:

properties in class AbstractPropertied

toString

public String toString()

Overrides:

toString in class Object

appendContents

protected void appendContents(StringBuilder buf)

typeString

public abstract String typeString()

Description copied from interface: ColumnMetadata

Converts type metadata into string representation accepted by the table schema parser.

Specified by:

typeString in interface ColumnMetadata

Returns:

type metadata string representation

columnString

public String columnString()

Description copied from interface: ColumnMetadata

Converts column metadata into string representation accepted by the table schema parser.

Specified by:

columnString in interface ColumnMetadata

Returns:

column metadata string representation

equals

public boolean equals(Object o)

Overrides:

equals in class AbstractPropertied

equalsWithProperties

public boolean equalsWithProperties(Object o)

escapeSpecialSymbols

protected String escapeSpecialSymbols(String value)

If given value contains backticks (`) or backslashes (\), escapes them.

Parameters:

value - string value

Returns:

updated value