Package gudusoft.gsqlparser.resolver2.expansion

Class ExpansionResult

Object
gudusoft.gsqlparser.resolver2.expansion.ExpansionResult
public class ExpansionResult extends Object
Result of star column expansion.

Tracks: - Which star columns were expanded - Which star columns could not be expanded (and why) - Non-star columns (passed through) - Statistics about the expansion

Example: 

 SELECT t1.*, t2.id, t3.*
 FROM t1 JOIN t2 JOIN t3

 ExpansionResult:
 - expandedStars: {t1.* -> [t1.id, t1.name], t3.* -> [t3.id, t3.status]}
 - nonStarColumns: [t2.id]
 - unexpandableStars: {}

  • Constructor Details

  • Method Details

    • addExpandedStar

      public void addExpandedStar(TResultColumn starColumn, List<ExpandedColumn> expandedColumns)
      Add a successfully expanded star column.
      Parameters:
      starColumn - the original star column
      expandedColumns - the expanded columns

    • addUnexpandableStar

      public void addUnexpandableStar(TResultColumn starColumn, String reason)
      Add a star column that could not be expanded.
      Parameters:
      starColumn - the star column
      reason - why it could not be expanded

    • addNonStarColumn

      public void addNonStarColumn(TResultColumn column)
      Add a non-star column.
      Parameters:
      column - the non-star column

    • getExpandedStars

      public Map<TResultColumn,List<ExpandedColumn>> getExpandedStars()
      Get all expanded stars.
      Returns:
      map of star column to expanded columns

    • getUnexpandableStars

      public Map<TResultColumn,String> getUnexpandableStars()
      Get all unexpandable stars.
      Returns:
      map of star column to reason

    • getNonStarColumns

      public List<TResultColumn> getNonStarColumns()
      Get all non-star columns.
      Returns:
      list of non-star columns

    • getAllExpandedColumns

      public List<ExpandedColumn> getAllExpandedColumns()
      Get all expanded columns (flattened list).
      Returns:
      all expanded columns from all stars

    • getTotalColumnCount

      public int getTotalColumnCount()
      Get the total number of columns after expansion. This includes expanded star columns and non-star columns.
      Returns:
      total column count

    • getExpandedStarCount

      public int getExpandedStarCount()
      Get the number of star columns that were expanded.
      Returns:
      expanded star count

    • getUnexpandableStarCount

      public int getUnexpandableStarCount()
      Get the number of star columns that could not be expanded.
      Returns:
      unexpandable star count

    • isFullyExpanded

      public boolean isFullyExpanded()
      Check if all stars were successfully expanded.
      Returns:
      true if no unexpandable stars, false otherwise

    • hasExpandedStars

      public boolean hasExpandedStars()
      Check if any stars were expanded.
      Returns:
      true if at least one star was expanded

    • getStatistics

      public String getStatistics()
      Get statistics about the expansion.
      Returns:
      statistics string

    • toString

      public String toString()
      Overrides:
      toString in class Object