Package org.apache.calcite.sql.dialect

Class MssqlSqlDialect

java.lang.Object

org.apache.calcite.sql.SqlDialect

org.apache.calcite.sql.dialect.MssqlSqlDialect

public class MssqlSqlDialect
extends SqlDialect

A SqlDialect implementation for the Microsoft SQL Server 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 final SqlDialect	DEFAULT
static final SqlDialect.Context	DEFAULT_CONTEXT
static final RelDataTypeSystem	MSSQL_TYPE_SYSTEM	Mssql type system.

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

BUILT_IN_OPERATORS_LIST, EMPTY_CONTEXT, identifierEndQuoteString, identifierEscapedQuote, identifierQuoteString, literalEndQuoteString, literalEscapedQuote, literalQuoteString, LOGGER, nullCollation

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method	Description
@Nullable SqlNode	emulateNullDirection(SqlNode node, boolean nullsFirst, boolean desc)	Returns the SqlNode for emulating the null direction for the given field or null if no emulation needs to be done.
boolean	supportsApproxCountDistinct()	Returns whether this dialect supports APPROX_COUNT_DISTINCT functions.
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`.
boolean	supportsGroupByWithCube()	Returns whether this dialect supports "WITH CUBE" in "GROUP BY" clause.
boolean	supportsGroupByWithRollup()	Returns whether this dialect supports "WITH ROLLUP" in the "GROUP BY" clause.
void	unparseBoolLiteral(SqlWriter writer, SqlLiteral literal, int leftPrec, int rightPrec)
void	unparseCall(SqlWriter writer, SqlCall call, int leftPrec, int rightPrec)
void	unparseDateTimeLiteral(SqlWriter writer, SqlAbstractDateTimeLiteral literal, int leftPrec, int rightPrec)
void	unparseOffsetFetch(SqlWriter writer, @Nullable SqlNode offset, @Nullable SqlNode fetch)	Converts an offset and fetch into SQL.
void	unparseSqlDatetimeArithmetic(SqlWriter writer, SqlCall call, SqlKind sqlKind, int leftPrec, int rightPrec)
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.
void	unparseTopN(SqlWriter writer, @Nullable SqlNode offset, @Nullable SqlNode fetch)	Converts a fetch into a "SELECT TOP(fetch)".

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

allowsAs, configureParser, configureParser, containsNonAscii, create, defaultNullDirection, emulateJoinTypeForCrossJoin, emulateNullDirectionWithIsNull, getCalendarPolicy, getCastSpec, getConformance, getDatabaseProduct, getFormatModel, getNullCollation, getProduct, getQuotedCasing, getQuoting, getSingleRowTableName, getTypeSystem, getUnquotedCasing, hasImplicitTableAlias, identifierNeedsQuote, isCaseSensitive, prepareUnparse, quoteIdentifier, quoteIdentifier, quoteIdentifier, quoteStringLiteral, quoteStringLiteral, quoteStringLiteralUnicode, quoteTimestampLiteral, requiresAliasForFromItems, rewriteMaxMin, rewriteMaxMinExpr, rewriteSingleValueExpr, supportBooleanCaseWhen, supportGenerateSelectStar, supportsAggregateFunction, supportsAggregateFunctionFilter, supportsAliasedValues, supportsDataType, supportsFunction, supportsGroupByLiteral, supportsImplicitTypeCoercion, supportsJoinType, supportsNestedAggregations, supportsOffsetFetch, supportsOrderByLiteral, supportsTimestampPrecision, supportsWindowFunctions, unparseFetchUsingAnsi, unparseFetchUsingLimit, unparseLimit, unparseNumericLiteral, unparseOffset, unparseSqlSetOption, unparseTableScanHints, unquoteStringLiteral

Methods inherited from class java.lang.Object

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

Field Details

MSSQL_TYPE_SYSTEM

public static final RelDataTypeSystem MSSQL_TYPE_SYSTEM

Mssql type system.

DEFAULT_CONTEXT

public static final SqlDialect.Context DEFAULT_CONTEXT

DEFAULT

public static final SqlDialect DEFAULT

Constructor Details

MssqlSqlDialect

public MssqlSqlDialect(SqlDialect.Context context)

Creates a MssqlSqlDialect.

Method Details

emulateNullDirection

public @Nullable SqlNode emulateNullDirection(SqlNode node,
 boolean nullsFirst,
 boolean desc)

Returns the SqlNode for emulating the null direction for the given field or null if no emulation needs to be done.

MSSQL does not support NULLS FIRST, so we emulate using CASE expressions. For example,

ORDER BY x NULLS FIRST

becomes

ORDER BY CASE WHEN x IS NULL THEN 0 ELSE 1 END, x

Overrides:

emulateNullDirection in class SqlDialect

Parameters:

node - The SqlNode representing the expression

nullsFirst - Whether nulls should come first

desc - Whether the sort direction is RelFieldCollation.Direction.DESCENDING or RelFieldCollation.Direction.STRICTLY_DESCENDING

Returns:

A SqlNode for null direction emulation or null if not required

unparseOffsetFetch

public void unparseOffsetFetch(SqlWriter writer,
 @Nullable SqlNode offset,
 @Nullable SqlNode fetch)

Description copied from class: SqlDialect

Converts an offset and fetch into SQL.

At least one of offset and fetch must be provided.

Common options:

• OFFSET offset ROWS FETCH NEXT fetch ROWS ONLY (ANSI standard SQL, Oracle, PostgreSQL, and the default)
• LIMIT fetch OFFSET offset (Apache Hive, MySQL, Redshift)

Overrides:

unparseOffsetFetch in class SqlDialect

Parameters:

writer - Writer

offset - Number of rows to skip before emitting, or null

fetch - Number of rows to fetch, or null

See Also:

• SqlDialect.unparseFetchUsingAnsi(SqlWriter, SqlNode, SqlNode)
• SqlDialect.unparseFetchUsingLimit(SqlWriter, SqlNode, SqlNode)

unparseTopN

public void unparseTopN(SqlWriter writer,
 @Nullable SqlNode offset,
 @Nullable SqlNode fetch)

Description copied from class: SqlDialect

Converts a fetch into a "SELECT TOP(fetch)".

A dialect that uses "TOP" syntax should override this method to print "TOP(fetch)", and override SqlDialect.unparseOffsetFetch(org.apache.calcite.sql.SqlWriter, org.apache.calcite.sql.SqlNode, org.apache.calcite.sql.SqlNode) to no-op.

The default implementation of this method is no-op.

Overrides:

unparseTopN in class SqlDialect

Parameters:

writer - Writer

offset - Number of rows to skip before emitting, or null

fetch - Number of rows to fetch, or null

unparseDateTimeLiteral

public void unparseDateTimeLiteral(SqlWriter writer,
 SqlAbstractDateTimeLiteral literal,
 int leftPrec,
 int rightPrec)

Overrides:

unparseDateTimeLiteral in class SqlDialect

unparseCall

public void unparseCall(SqlWriter writer,
 SqlCall call,
 int leftPrec,
 int rightPrec)

Overrides:

unparseCall in class SqlDialect

unparseBoolLiteral

public void unparseBoolLiteral(SqlWriter writer,
 SqlLiteral literal,
 int leftPrec,
 int rightPrec)

Overrides:

unparseBoolLiteral in class SqlDialect

supportsApproxCountDistinct

public boolean supportsApproxCountDistinct()

Description copied from class: SqlDialect

Returns whether this dialect supports APPROX_COUNT_DISTINCT functions.

Overrides:

supportsApproxCountDistinct in class SqlDialect

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

supportsGroupByWithRollup

public boolean supportsGroupByWithRollup()

Description copied from class: SqlDialect

Returns whether this dialect supports "WITH ROLLUP" in the "GROUP BY" clause.

For instance, in MySQL version 5,

SELECT deptno, job, COUNT(*) AS c FROM emp GROUP BY deptno, job WITH ROLLUP

is equivalent to standard SQL

SELECT deptno, job, COUNT(*) AS c FROM emp GROUP BY ROLLUP(deptno, job) ORDER BY deptno, job

The "WITH ROLLUP" clause was introduced in MySQL and is not standard SQL.

See also SqlDialect.supportsAggregateFunction(SqlKind) applied to SqlKind.ROLLUP, which returns true in MySQL 8 and higher.

Overrides:

supportsGroupByWithRollup in class SqlDialect

supportsGroupByWithCube

public boolean supportsGroupByWithCube()

Description copied from class: SqlDialect

Returns whether this dialect supports "WITH CUBE" in "GROUP BY" clause.

Overrides:

supportsGroupByWithCube in class SqlDialect

unparseSqlDatetimeArithmetic

public void unparseSqlDatetimeArithmetic(SqlWriter writer,
 SqlCall call,
 SqlKind sqlKind,
 int leftPrec,
 int rightPrec)

Overrides:

unparseSqlDatetimeArithmetic 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