Package org.apache.iceberg

Interface Scan<ThisT,​T extends ScanTask,​G extends ScanTaskGroup<T>>

    • Method Detail

      • option

        ThisT option​(java.lang.String property,
             java.lang.String value)
        Create a new scan from this scan's configuration that will override the Table's behavior based on the incoming pair. Unknown properties will be ignored.
        Parameters:
        property - name of the table property to be overridden
        value - value to override with
        Returns:
        a new scan based on this with overridden behavior

      • project

        ThisT project​(Schema schema)
        Create a new scan from this with the schema as its projection.
        Parameters:
        schema - a projection schema
        Returns:
        a new scan based on this with the given projection

      • caseSensitive

        ThisT caseSensitive​(boolean caseSensitive)
        Create a new scan from this that, if data columns where selected via select(java.util.Collection), controls whether the match to the schema will be done with case sensitivity. Default is true.
        Returns:
        a new scan based on this with case sensitivity as stated

      • isCaseSensitive

        boolean isCaseSensitive()
        Returns whether this scan is case-sensitive with respect to column names.
        Returns:
        true if case-sensitive, false otherwise.

      • includeColumnStats

        ThisT includeColumnStats()
        Create a new scan from this that loads the column stats with each data file.

        Column stats include: value count, null value count, lower bounds, and upper bounds.

        Returns:
        a new scan based on this that loads column stats.

      • select

        ThisT select​(java.util.Collection<java.lang.String> columns)
        Create a new scan from this that will read the given data columns. This produces an expected schema that includes all fields that are either selected or used by this scan's filter expression.
        Parameters:
        columns - column names from the table's schema
        Returns:
        a new scan based on this with the given projection columns

      • select

        default ThisT select​(java.lang.String... columns)
        Create a new scan from this that will read the given columns. This produces an expected schema that includes all fields that are either selected or used by this scan's filter expression.
        Parameters:
        columns - column names
        Returns:
        a new scan based on this with the given projection columns

      • filter

        ThisT filter​(Expression expr)
        Create a new scan from the results of this filtered by the Expression.
        Parameters:
        expr - a filter expression
        Returns:
        a new scan based on this with results filtered by the expression

      • filter

        Expression filter()
        Returns this scan's filter Expression.
        Returns:
        this scan's filter expression

      • ignoreResiduals

        ThisT ignoreResiduals()
        Create a new scan from this that applies data filtering to files but not to rows in those files.
        Returns:
        a new scan based on this that does not filter rows in files.

      • planWith

        ThisT planWith​(java.util.concurrent.ExecutorService executorService)
        Create a new scan to use a particular executor to plan. The default worker pool will be used by default.
        Parameters:
        executorService - the provided executor
        Returns:
        a table scan that uses the provided executor to access manifests

      • schema

        Schema schema()
        Returns this scan's projection Schema.

        If the projection schema was set directly using project(Schema), returns that schema.

        If the projection schema was set by calling select(Collection), returns a projection schema that includes the selected data fields and any fields used in the filter expression.

        Returns:
        this scan's projection schema

      • planFiles

        CloseableIterable<T> planFiles()
        Plan tasks for this scan where each task reads a single file.

        Use planTasks() for planning balanced tasks where each task will read either a single file, a part of a file, or multiple files.

        Returns:
        an Iterable of tasks scanning entire files required by this scan

      • planTasks

        CloseableIterable<G> planTasks()
        Plan balanced task groups for this scan by splitting large and combining small tasks.

        Task groups created by this method may read partial input files, multiple input files or both.

        Returns:
        an Iterable of balanced task groups required by this scan

      • targetSplitSize

        long targetSplitSize()
        Returns the target split size for this scan.

      • splitLookback

        int splitLookback()
        Returns the split lookback for this scan.

      • splitOpenFileCost

        long splitOpenFileCost()
        Returns the split open file cost for this scan.