Class SqlAlter

All Implemented Interfaces:
Cloneable
Direct Known Subclasses:
SqlSetOption

public abstract class SqlAlter extends SqlCall
Base class for an ALTER statements parse tree nodes. The portion of the statement covered by this class is "ALTER <SCOPE>. Subclasses handle whatever comes after the scope.
  • Constructor Details

  • Method Details

    • unparse

      public final void unparse(SqlWriter writer, int leftPrec, int rightPrec)
      Description copied from class: SqlNode
      Writes a SQL representation of this node to a writer.

      The leftPrec and rightPrec parameters give us enough context to decide whether we need to enclose the expression in parentheses. For example, we need parentheses around "2 + 3" if preceded by "5 *". This is because the precedence of the "*" operator is greater than the precedence of the "+" operator.

      The algorithm handles left- and right-associative operators by giving them slightly different left- and right-precedence.

      If SqlWriter.isAlwaysUseParentheses() is true, we use parentheses even when they are not required by the precedence rules.

      For the details of this algorithm, see SqlCall.unparse(org.apache.calcite.sql.SqlWriter, int, int).

      Overrides:
      unparse in class SqlCall
      Parameters:
      writer - Target writer
      leftPrec - The precedence of the SqlNode immediately preceding this node in a depth-first scan of the parse tree
      rightPrec - The precedence of the SqlNode immediately
    • unparseAlterOperation

      protected abstract void unparseAlterOperation(SqlWriter writer, int leftPrec, int rightPrec)
    • getScope

      public @Nullable String getScope()
    • setScope

      public void setScope(@Nullable String scope)