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Fix Javadocs in ColumnCapablities.java (#17462)

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Virushade 2024-11-12 14:00:33 +08:00 committed by GitHub
parent 3f56b57c7e
commit 8278a1f7df
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1 changed files with 10 additions and 10 deletions
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processing/src/main/java/org/apache/druid/segment/column/ColumnCapabilities.java
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@ -38,13 +38,13 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
/**
* Is the column dictionary encoded? If so, a DimensionDictionarySelector may be used instead of using a value
* selector, allowing algorithms to operate on primitive integer dictionary ids rather than the looked up dictionary
* values
* values.
*/
Capable isDictionaryEncoded();
/**
* If the column is dictionary encoded, are those values sorted? Useful to know for optimizations that can defer
* looking up values and allowing sorting with the dictionary ids directly
* looking up values and allowing sorting with the dictionary ids directly.
*/
Capable areDictionaryValuesSorted();
@ -52,20 +52,20 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
/**
* If the column is dictionary encoded, is there a 1:1 mapping of dictionary ids to values? If this is true, it
* unlocks optimizations such as allowing for things like grouping directly on dictionary ids and deferred value
* lookup
* lookup.
*/
Capable areDictionaryValuesUnique();
/**
* String columns are sneaky, and might have multiple values, this is to allow callers to know and appropriately
* prepare themselves
* prepare themselves.
*/
Capable hasMultipleValues();
/**
* Does the column have an inverted index bitmap for each value? If so, these may be employed to 'pre-filter' the
* column by examining if the values match the filter and intersecting the bitmaps, to avoid having to scan and
* evaluate if every row matches the filter
* evaluate if every row matches the filter.
*/
boolean hasBitmapIndexes();
@ -76,7 +76,7 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
/**
* Does this column contain null values? If so, callers, especially for primitive numeric columns, will need to check
* for null value rows and act accordingly
* for null value rows and act accordingly.
*/
Capable hasNulls();
@ -164,7 +164,7 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
}
/**
* This interface defines the shape of a mechnism to allow for bespoke coercion of {@link Capable#UNKNOWN} into
* This interface defines the shape of a mechanism to allow for bespoke coercion of {@link Capable#UNKNOWN} into
* {@link Capable#TRUE} or {@link Capable#FALSE} for each {@link Capable} of a {@link ColumnCapabilities}, as is
* appropriate for the situation of the caller.
*/
@ -177,13 +177,13 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
boolean dictionaryEncoded();
/**
* If {@link ColumnCapabilities#areDictionaryValuesSorted()} ()} is {@link Capable#UNKNOWN}, define if it should be
* If {@link ColumnCapabilities#areDictionaryValuesSorted()} is {@link Capable#UNKNOWN}, define if it should be
* treated as true or false.
*/
boolean dictionaryValuesSorted();
/**
* If {@link ColumnCapabilities#areDictionaryValuesUnique()} ()} is {@link Capable#UNKNOWN}, define if it should be
* If {@link ColumnCapabilities#areDictionaryValuesUnique()} is {@link Capable#UNKNOWN}, define if it should be
* treated as true or false.
*/
boolean dictionaryValuesUnique();
@ -196,7 +196,7 @@ public interface ColumnCapabilities extends TypeSignature<ValueType>
/**
* If {@link ColumnCapabilities#hasNulls()} is {@link Capable#UNKNOWN}, define if it should be treated as true
* or false
* or false.
*/
boolean hasNulls();
}