Package dev.frostlake.executor.expressions

Class ConnectByRootExpression

java.lang.Object

dev.frostlake.executor.expressions.ColumnReferenceExpression

dev.frostlake.executor.expressions.ConnectByRootExpression

All Implemented Interfaces:

Expression

public class ConnectByRootExpression
extends ColumnReferenceExpression

CONNECT_BY_ROOT <column>: the column's value on the ROOT row of the hierarchy branch that produced the current row.

The CONNECT BY expansion materializes the root row's values as extra ROOT_PREFIX-prefixed columns (hidden from SELECT *), so this is modelled as an ordinary ColumnReferenceExpression to that prefixed name. Used in a query WITHOUT a CONNECT BY clause the prefixed column is absent and Snowflake simply returns the column's own value (live-verified: SELECT CONNECT_BY_ROOT nm FROM h returns every row's nm) — baseColumnReference() is the fallback the evaluator uses for that case.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	ROOT_PREFIX	Prefix of the synthesized root-row column names produced by the CONNECT BY expansion.

Constructor Summary

Constructors

Constructor	Description
ConnectByRootExpression(String baseTableName, String baseColumnName)

Method Summary

Modifier and Type	Method	Description
ColumnReferenceExpression	baseColumnReference()	The plain column reference as written after CONNECT_BY_ROOT.
String	toString()

Methods inherited from class dev.frostlake.executor.expressions.ColumnReferenceExpression

accept, describeStar, getColumnName, getPosition, getPositionalOrdinal, getStarArgument, getTableName, getWrittenName, isQualified, setWrittenName

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

ROOT_PREFIX

public static final String ROOT_PREFIX

Prefix of the synthesized root-row column names produced by the CONNECT BY expansion.

See Also:

• Constant Field Values

Constructor Details

ConnectByRootExpression

public ConnectByRootExpression(String baseTableName,
 String baseColumnName)

Method Details

baseColumnReference

public ColumnReferenceExpression baseColumnReference()

The plain column reference as written after CONNECT_BY_ROOT.

toString

public String toString()

Overrides:

toString in class ColumnReferenceExpression