org.eigenbase.sql
Class SqlIntervalLiteral

java.lang.Object
  org.eigenbase.sql.SqlNode
      org.eigenbase.sql.SqlLiteral
          org.eigenbase.sql.SqlIntervalLiteral

All Implemented Interfaces:

Cloneable

public class SqlIntervalLiteral
extends SqlLiteral

A SQL literal representing a time interval.

Examples:

• INTERVAL '1' SECOND
• INTERVAL '1:00:05.345' HOUR
• INTERVAL '3:4' YEAR TO MONTH

YEAR/MONTH intervals are not implemented yet.

The interval string, such as '1:00:05.345', is not parsed yet.

Version:

$Id: //open/dev/farrago/src/org/eigenbase/sql/SqlIntervalLiteral.java#16 $

Author:

jhyde

Nested Class Summary

static class

SqlIntervalLiteral.IntervalValue A Interval value.

Nested classes/interfaces inherited from class org.eigenbase.sql.SqlLiteral

SqlLiteral.SqlSymbol

Field Summary

Fields inherited from class org.eigenbase.sql.SqlLiteral

value

Fields inherited from class org.eigenbase.sql.SqlNode

emptyArray

Constructor Summary

protected	SqlIntervalLiteral(int sign, String intervalStr, SqlIntervalQualifier intervalQualifier, SqlTypeName sqlTypeName, SqlParserPos pos)
private	SqlIntervalLiteral(SqlIntervalLiteral.IntervalValue intervalValue, SqlTypeName sqlTypeName, SqlParserPos pos)

Method Summary

SqlNode	clone(SqlParserPos pos) Clones a SqlNode with a different position.
void	unparse(SqlWriter writer, int leftPrec, int rightPrec) Writes a SQL representation of this node to a writer.

Methods inherited from class org.eigenbase.sql.SqlLiteral

accept, bigDecimalValue, booleanValue, createApproxNumeric, createBinaryString, createBinaryString, createBoolean, createCharString, createCharString, createDate, createExactNumeric, createInterval, createNegative, createNull, createSample, createSqlType, createSymbol, createTime, createTimestamp, createUnknown, equals, equalsDeep, getKind, getMonotonicity, getStringValue, getTypeName, getValue, hashCode, intValue, longValue, sampleValue, stringValue, symbolValue, toValue, unescapeUnicode, validate, valueMatchesType

Methods inherited from class org.eigenbase.sql.SqlNode

clone, cloneArray, equalDeep, findValidOptions, getParserPosition, isA, toSqlString, toSqlString, toString, validateExpr

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SqlIntervalLiteral

protected SqlIntervalLiteral(int sign,
                             String intervalStr,
                             SqlIntervalQualifier intervalQualifier,
                             SqlTypeName sqlTypeName,
                             SqlParserPos pos)

SqlIntervalLiteral

private SqlIntervalLiteral(SqlIntervalLiteral.IntervalValue intervalValue,
                           SqlTypeName sqlTypeName,
                           SqlParserPos pos)

Method Detail

clone

public SqlNode clone(SqlParserPos pos)

Description copied from class: SqlNode

Clones a SqlNode with a different position.

Overrides:

clone in class SqlLiteral

unparse

public 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.eigenbase.sql.SqlWriter, int, int).

Overrides:

unparse in class SqlLiteral

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