Package org.h2.expression

Class Wildcard

java.lang.Object
org.h2.expression.Expression
org.h2.expression.Wildcard
All Implemented Interfaces:
HasSQL, Typed
public final class Wildcard extends Expression
A wildcard expression as in SELECT * FROM TEST. This object is only used temporarily during the parsing phase, and later replaced by column expressions.

  • Constructor Details

  • Method Details

    • getExceptColumns

      public ArrayList<ExpressionColumn> getExceptColumns()

    • setExceptColumns

      public void setExceptColumns(ArrayList<ExpressionColumn> exceptColumns)

    • mapExceptColumns

      public HashMap<Column,ExpressionColumn> mapExceptColumns()
      Returns map of excluded table columns to expression columns and validates that all columns are resolved and not duplicated.
      Returns:
      map of excluded table columns to expression columns

    • getValue

      public Value getValue(SessionLocal session)
      Description copied from class: Expression
      Return the resulting value for the current row.
      Specified by:
      getValue in class Expression
      Parameters:
      session - the session
      Returns:
      the result

    • getType

      public TypeInfo getType()
      Description copied from class: Expression
      Returns the data type. The data type may be unknown before the optimization phase.
      Specified by:
      getType in interface Typed
      Specified by:
      getType in class Expression
      Returns:
      the data type

    • mapColumns

      public void mapColumns(ColumnResolver resolver, int level, int state)
      Description copied from class: Expression
      Map the columns of the resolver to expression columns.
      Specified by:
      mapColumns in class Expression
      Parameters:
      resolver - the column resolver
      level - the subquery nesting level
      state - current state for nesting checks, initial value is Expression.MAP_INITIAL

    • optimize

      public Expression optimize(SessionLocal session)
      Description copied from class: Expression
      Try to optimize the expression.
      Specified by:
      optimize in class Expression
      Parameters:
      session - the session
      Returns:
      the optimized expression

    • setEvaluatable

      public void setEvaluatable(TableFilter tableFilter, boolean b)
      Description copied from class: Expression
      Tell the expression columns whether the table filter can return values now. This is used when optimizing the query.
      Specified by:
      setEvaluatable in class Expression
      Parameters:
      tableFilter - the table filter
      b - true if the table filter can return value

    • getTableAlias

      public String getTableAlias()
      Description copied from class: Expression
      Get the table alias name or null if this expression does not represent a column.
      Overrides:
      getTableAlias in class Expression
      Returns:
      the table alias name

    • getSchemaName

      public String getSchemaName()
      Description copied from class: Expression
      Get the schema name, or null
      Overrides:
      getSchemaName in class Expression
      Returns:
      the schema name

    • getUnenclosedSQL

      public StringBuilder getUnenclosedSQL(StringBuilder builder, int sqlFlags)
      Description copied from class: Expression
      Get the SQL statement of this expression. This may not always be the original SQL statement, especially after optimization. Enclosing '(' and ')' are never appended.
      Specified by:
      getUnenclosedSQL in class Expression
      Parameters:
      builder - string builder
      sqlFlags - formatting flags
      Returns:
      the specified string builder

    • updateAggregate

      public void updateAggregate(SessionLocal session, int stage)
      Description copied from class: Expression
      Update an aggregate value. This method is called at statement execution time. It is usually called once for each row, but if the expression is used multiple times (for example in the column list, and as part of the HAVING expression) it is called multiple times - the row counter needs to be used to make sure the internal state is only updated once.
      Specified by:
      updateAggregate in class Expression
      Parameters:
      session - the session
      stage - select stage

    • isEverything

      public boolean isEverything(ExpressionVisitor visitor)
      Description copied from class: Expression
      Check if this expression and all sub-expressions can fulfill a criteria. If any part returns false, the result is false.
      Specified by:
      isEverything in class Expression
      Parameters:
      visitor - the visitor
      Returns:
      if the criteria can be fulfilled

    • getCost

      public int getCost()
      Description copied from class: Expression
      Estimate the cost to process the expression. Used when optimizing the query, to calculate the query plan with the lowest estimated cost.
      Specified by:
      getCost in class Expression
      Returns:
      the estimated cost