Package org.apache.parquet.format
Enum ColumnIndex._Fields
- All Implemented Interfaces:
Serializable,Comparable<ColumnIndex._Fields>,org.apache.thrift.TFieldIdEnum
- Enclosing class:
- ColumnIndex
public static enum ColumnIndex._Fields
extends Enum<ColumnIndex._Fields>
implements org.apache.thrift.TFieldIdEnum
The set of fields this struct contains, along with convenience methods for finding and manipulating them.
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Enum Constant Summary
Enum ConstantsEnum ConstantDescriptionStores whether both min_values and max_values are ordered and if so, in which direction.Same as repetition_level_histograms except for definitions levels.Two lists containing lower and upper bounds for the values of each page determined by the ColumnOrder of the column.A list containing the number of NaN values for each page.A list containing the number of null values for each page Writers SHOULD always write this field even if no null values are present or the column is not nullable.A list of Boolean values to determine the validity of the corresponding min and max values.Contains repetition level histograms for each page concatenated together. -
Method Summary
Modifier and TypeMethodDescriptionstatic ColumnIndex._FieldsfindByName(String name) Find the _Fields constant that matches name, or null if its not found.static ColumnIndex._FieldsfindByThriftId(int fieldId) Find the _Fields constant that matches fieldId, or null if its not found.static ColumnIndex._FieldsfindByThriftIdOrThrow(int fieldId) Find the _Fields constant that matches fieldId, throwing an exception if it is not found.shortstatic ColumnIndex._FieldsReturns the enum constant of this type with the specified name.static ColumnIndex._Fields[]values()Returns an array containing the constants of this enum type, in the order they are declared.
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Enum Constant Details
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NULL_PAGES
A list of Boolean values to determine the validity of the corresponding min and max values. If true, a page contains only null values, and writers have to set the corresponding entries in min_values and max_values to byte[0], so that all lists have the same length. If false, the corresponding entries in min_values and max_values must be valid. -
MIN_VALUES
Two lists containing lower and upper bounds for the values of each page determined by the ColumnOrder of the column. These may be the actual minimum and maximum values found on a page, but can also be (more compact) values that do not exist on a page. For example, instead of storing "Blart Versenwald III", a writer may set min_values[i]="B", max_values[i]="C". Such more compact values must still be valid values within the column's logical type. Readers must make sure that list entries are populated before using them by inspecting null_pages. For columns of physical type FLOAT or DOUBLE, or logical type FLOAT16, NaN values are not to be included in these bounds. If all non-null values of a page are NaN, then a writer must do the following: - If the order of this column is TYPE_ORDER, then a column index must not be written for this column chunk. While this is unfortunate for performance, it is necessary to avoid conflict with legacy files that still included NaN in min_values and max_values even if the page had non-NaN values. To mitigate this, IEEE754_TOTAL_ORDER is recommended. - If the order of this column is IEEE754_TOTAL_ORDER, then min_values[i] and max_values[i] of that page must be set to the smallest and largest NaN values as defined by IEEE 754 total order. -
MAX_VALUES
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BOUNDARY_ORDER
Stores whether both min_values and max_values are ordered and if so, in which direction. This allows readers to perform binary searches in both lists. Readers cannot assume that max_values[i] <= min_values[i+1], even if the lists are ordered.- See Also:
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NULL_COUNTS
A list containing the number of null values for each page Writers SHOULD always write this field even if no null values are present or the column is not nullable. Readers MUST distinguish between null_counts not being present and null_count being 0. If null_counts are not present, readers MUST NOT assume all null counts are 0. -
REPETITION_LEVEL_HISTOGRAMS
Contains repetition level histograms for each page concatenated together. The repetition_level_histogram field on SizeStatistics contains more details. When present the length should always be (number of pages * (max_repetition_level + 1)) elements. Element 0 is the first element of the histogram for the first page. Element (max_repetition_level + 1) is the first element of the histogram for the second page. -
DEFINITION_LEVEL_HISTOGRAMS
Same as repetition_level_histograms except for definitions levels. -
NAN_COUNTS
A list containing the number of NaN values for each page. Only present for columns of physical type FLOAT or DOUBLE, or logical type FLOAT16. If this field is not present, readers MUST assume that there might be NaN values in any page.
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Method Details
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values
Returns an array containing the constants of this enum type, in the order they are declared.- Returns:
- an array containing the constants of this enum type, in the order they are declared
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valueOf
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)- Parameters:
name- the name of the enum constant to be returned.- Returns:
- the enum constant with the specified name
- Throws:
IllegalArgumentException- if this enum type has no constant with the specified nameNullPointerException- if the argument is null
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findByThriftId
Find the _Fields constant that matches fieldId, or null if its not found. -
findByThriftIdOrThrow
Find the _Fields constant that matches fieldId, throwing an exception if it is not found. -
findByName
Find the _Fields constant that matches name, or null if its not found. -
getThriftFieldId
public short getThriftFieldId()- Specified by:
getThriftFieldIdin interfaceorg.apache.thrift.TFieldIdEnum
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getFieldName
- Specified by:
getFieldNamein interfaceorg.apache.thrift.TFieldIdEnum
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