Package org.apache.calcite.sql.dialect

Class Db2SqlDialect

java.lang.Object

org.apache.calcite.sql.SqlDialect

org.apache.calcite.sql.dialect.Db2SqlDialect

public class Db2SqlDialect
extends SqlDialect

A SqlDialect implementation for the IBM DB2 database.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.calcite.sql.SqlDialect

SqlDialect.CalendarPolicy, SqlDialect.Context, SqlDialect.DatabaseProduct, SqlDialect.FakeUtil

Field Summary

Fields

Modifier and Type	Field	Description
static SqlDialect	DEFAULT

Fields inherited from class org.apache.calcite.sql.SqlDialect

BUILT_IN_OPERATORS_LIST, CALCITE, DUMMY, EMPTY_CONTEXT, LOGGER, nullCollation

Constructor Summary

Constructors

Constructor	Description
Db2SqlDialect(SqlDialect.Context context)	Creates a Db2SqlDialect.

Method Summary

Modifier and Type	Method	Description
boolean	hasImplicitTableAlias()	Returns whether a qualified table in the FROM clause has an implicit alias which consists of just the table name.
boolean	supportsCharSet()	Returns whether the dialect supports character set names as part of a data type, for instance VARCHAR(30) CHARACTER SET `ISO-8859-1`.
void	unparseSqlIntervalLiteral(SqlWriter writer, SqlIntervalLiteral literal, int leftPrec, int rightPrec)	Converts an interval literal to a SQL string.
void	unparseSqlIntervalQualifier(SqlWriter writer, SqlIntervalQualifier qualifier, RelDataTypeSystem typeSystem)	Converts an interval qualifier to a SQL string.

Methods inherited from class org.apache.calcite.sql.SqlDialect

allowsAs, create, defaultNullDirection, emptyContext, emulateNullDirection, emulateNullDirectionWithIsNull, getCalendarPolicy, getCastSpec, getDatabaseProduct, getNullCollation, getProduct, getTypeSystem, identifierNeedsToBeQuoted, quoteIdentifier, quoteIdentifier, quoteIdentifier, quoteStringLiteral, quoteStringLiteralUnicode, quoteTimestampLiteral, requiresAliasForFromItems, rewriteSingleValueExpr, supportsAggregateFunction, supportsAliasedValues, supportsFunction, supportsNestedAggregations, supportsOffsetFetch, supportsWindowFunctions, unparseCall, unparseDateTimeLiteral, unparseFetchUsingAnsi, unparseFetchUsingLimit, unparseOffsetFetch, unparseSqlDatetimeArithmetic, unquoteStringLiteral

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT

public static final SqlDialect DEFAULT

Constructor Detail

Db2SqlDialect

public Db2SqlDialect(SqlDialect.Context context)

Creates a Db2SqlDialect.

Method Detail

supportsCharSet

public boolean supportsCharSet()

Description copied from class: SqlDialect

Returns whether the dialect supports character set names as part of a data type, for instance VARCHAR(30) CHARACTER SET `ISO-8859-1`.

Overrides:

supportsCharSet in class SqlDialect

hasImplicitTableAlias

public boolean hasImplicitTableAlias()

Description copied from class: SqlDialect

Returns whether a qualified table in the FROM clause has an implicit alias which consists of just the table name.

For example, in SqlDialect.DatabaseProduct.ORACLE

SELECT * FROM sales.emp

is equivalent to

SELECT * FROM sales.emp AS emp

and therefore

SELECT emp.empno FROM sales.emp

is valid. But SqlDialect.DatabaseProduct.DB2 does not have an implicit alias, so the previous query it not valid; you need to write

SELECT sales.emp.empno FROM sales.emp

Returns true for all databases except DB2.

Overrides:

hasImplicitTableAlias in class SqlDialect

unparseSqlIntervalQualifier

public void unparseSqlIntervalQualifier(SqlWriter writer,
                                        SqlIntervalQualifier qualifier,
                                        RelDataTypeSystem typeSystem)

Description copied from class: SqlDialect

Converts an interval qualifier to a SQL string. The default implementation returns strings such as INTERVAL '1 2:3:4' DAY(4) TO SECOND(4).

Overrides:

unparseSqlIntervalQualifier in class SqlDialect

unparseSqlIntervalLiteral

public void unparseSqlIntervalLiteral(SqlWriter writer,
                                      SqlIntervalLiteral literal,
                                      int leftPrec,
                                      int rightPrec)

Description copied from class: SqlDialect

Converts an interval literal to a SQL string. The default implementation returns strings such as INTERVAL '1 2:3:4' DAY(4) TO SECOND(4).

Overrides:

unparseSqlIntervalLiteral in class SqlDialect