java.lang.Object
- org.apache.calcite.sql.SqlDialect

Direct Known Subclasses:

AccessSqlDialect, AnsiSqlDialect, BigQuerySqlDialect, CalciteSqlDialect, Db2SqlDialect, DerbySqlDialect, FirebirdSqlDialect, H2SqlDialect, HiveSqlDialect, HsqldbSqlDialect, InfobrightSqlDialect, InformixSqlDialect, IngresSqlDialect, InterbaseSqlDialect, JethroDataSqlDialect, LucidDbSqlDialect, MssqlSqlDialect, MysqlSqlDialect, NeoviewSqlDialect, NetezzaSqlDialect, OracleSqlDialect, ParaccelSqlDialect, PhoenixSqlDialect, PostgresqlSqlDialect, RedshiftSqlDialect, SybaseSqlDialect, TeradataSqlDialect, VerticaSqlDialect
```
public class SqlDialect
extends java.lang.Object
```
SqlDialect encapsulates the differences between dialects of SQL.
It is used by classes such as SqlWriter and SqlBuilder.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`SqlDialect.CalendarPolicy`	Whether this JDBC driver needs you to pass a Calendar object to methods such as `ResultSet.getTimestamp(int, java.util.Calendar)`.
`static interface`	`SqlDialect.Context`	Information for creating a dialect.
`private static class`	`SqlDialect.ContextImpl`	Implementation of Context.
`static class`	`SqlDialect.DatabaseProduct`	Rough list of flavors of database.
`static class`	`SqlDialect.FakeUtil`	A few utility functions copied from org.apache.calcite.util.Util.

Field Summary

Fields
Modifier and Type	Field	Description
`protected static java.util.Set<SqlOperator>`	`BUILT_IN_OPERATORS_LIST`	Built-in scalar functions and operators common for every dialect.
`static SqlDialect`	`CALCITE`	Deprecated. Use `CalciteSqlDialect.DEFAULT` instead.
`private SqlDialect.DatabaseProduct`	`databaseProduct`
`private RelDataTypeSystem`	`dataTypeSystem`
`static SqlDialect`	`DUMMY`	Deprecated. Use `AnsiSqlDialect.DEFAULT` instead.
`static SqlDialect.Context`	`EMPTY_CONTEXT`	Empty context.
`private static char[]`	`HEXITS`
`private java.lang.String`	`identifierEndQuoteString`
`private java.lang.String`	`identifierEscapedQuote`
`private java.lang.String`	`identifierQuoteString`
`protected static org.slf4j.Logger`	`LOGGER`
`protected NullCollation`	`nullCollation`

Constructor Summary

Constructors
Constructor	Description
`SqlDialect(SqlDialect.Context context)`	Creates a SqlDialect.
`SqlDialect(SqlDialect.DatabaseProduct databaseProduct, java.lang.String databaseProductName, java.lang.String identifierQuoteString)`	Deprecated.
`SqlDialect(SqlDialect.DatabaseProduct databaseProduct, java.lang.String databaseProductName, java.lang.String identifierQuoteString, NullCollation nullCollation)`	Deprecated. Use `SqlDialect(Context)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`protected boolean`	`allowsAs()`
`private static boolean`	`containsNonAscii(java.lang.String s)`	Returns whether the string contains any characters outside the comfortable 7-bit ASCII range (32 through 127).
`static SqlDialect`	`create(java.sql.DatabaseMetaData databaseMetaData)`	Deprecated. Replaced by `SqlDialectFactory`
`RelFieldCollation.NullDirection`	`defaultNullDirection(RelFieldCollation.Direction direction)`	Returns whether NULL values are sorted first or last, in this dialect, in an ORDER BY item of a given direction.
`protected static SqlDialect.Context`	`emptyContext()`	Creates an empty context.
`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.
`protected SqlNode`	`emulateNullDirectionWithIsNull(SqlNode node, boolean nullsFirst, boolean desc)`
`SqlDialect.CalendarPolicy`	`getCalendarPolicy()`
`SqlNode`	`getCastSpec(RelDataType type)`
`SqlDialect.DatabaseProduct`	`getDatabaseProduct()`	Deprecated. To be removed without replacement
`NullCollation`	`getNullCollation()`	Returns how NULL values are sorted if an ORDER BY item does not contain NULLS ASCENDING or NULLS DESCENDING.
`static SqlDialect.DatabaseProduct`	`getProduct(java.lang.String productName, java.lang.String productVersion)`	Deprecated.
`RelDataTypeSystem`	`getTypeSystem()`	Returns the type system implementation for this dialect.
`boolean`	`hasImplicitTableAlias()`	Returns whether a qualified table in the FROM clause has an implicit alias which consists of just the table name.
`boolean`	`identifierNeedsToBeQuoted(java.lang.String val)`	Returns whether a given identifier needs to be quoted.
`java.lang.String`	`quoteIdentifier(java.lang.String val)`	Encloses an identifier in quotation marks appropriate for the current SQL dialect.
`java.lang.StringBuilder`	`quoteIdentifier(java.lang.StringBuilder buf, java.lang.String val)`	Encloses an identifier in quotation marks appropriate for the current SQL dialect, writing the result to a `StringBuilder`.
`java.lang.StringBuilder`	`quoteIdentifier(java.lang.StringBuilder buf, java.util.List<java.lang.String> identifiers)`	Quotes a multi-part identifier.
`java.lang.String`	`quoteStringLiteral(java.lang.String val)`	Converts a string into a string literal.
`void`	`quoteStringLiteralUnicode(java.lang.StringBuilder buf, java.lang.String val)`	Converts a string into a unicode string literal.
`java.lang.String`	`quoteTimestampLiteral(java.sql.Timestamp timestamp)`	Converts a timestamp to a SQL timestamp literal, e.g.
`protected boolean`	`requiresAliasForFromItems()`
`SqlNode`	`rewriteSingleValueExpr(SqlNode aggCall)`	Rewrite SINGLE_VALUE into expression based on database variants E.g.
`boolean`	`supportsAggregateFunction(SqlKind kind)`
`boolean`	`supportsAliasedValues()`	Returns whether the dialect supports VALUES in a sub-query with and an "AS t(column, ...)" values to define column names.
`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`	`supportsFunction(SqlOperator operator, RelDataType type, java.util.List<RelDataType> paramTypes)`	Returns whether this dialect supports a given function or operator.
`boolean`	`supportsNestedAggregations()`	Returns whether the dialect supports nested aggregations, for instance `SELECT SUM(SUM(1))` .
`boolean`	`supportsOffsetFetch()`	Deprecated. This method is no longer used.
`boolean`	`supportsWindowFunctions()`	Returns whether this dialect supports window functions (OVER clause).
`void`	`unparseCall(SqlWriter writer, SqlCall call, int leftPrec, int rightPrec)`
`void`	`unparseDateTimeLiteral(SqlWriter writer, SqlAbstractDateTimeLiteral literal, int leftPrec, int rightPrec)`
`protected void`	`unparseFetchUsingAnsi(SqlWriter writer, SqlNode offset, SqlNode fetch)`	Unparses offset/fetch using ANSI standard "OFFSET offset ROWS FETCH NEXT fetch ROWS ONLY" syntax.
`protected void`	`unparseFetchUsingLimit(SqlWriter writer, SqlNode offset, SqlNode fetch)`	Unparses offset/fetch using "LIMIT fetch OFFSET offset" syntax.
`void`	`unparseOffsetFetch(SqlWriter writer, SqlNode offset, 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.
`java.lang.String`	`unquoteStringLiteral(java.lang.String val)`	Converts a string literal back into a string.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - LOGGER
```
protected static final org.slf4j.Logger LOGGER
```
  - EMPTY_CONTEXT
```
public static final SqlDialect.Context EMPTY_CONTEXT
```
    Empty context.
  - DUMMY
```
@Deprecated
public static final SqlDialect DUMMY
```
    Deprecated.
    Use AnsiSqlDialect.DEFAULT instead.
  - CALCITE
```
@Deprecated
public static final SqlDialect CALCITE
```
    Deprecated.
    Use CalciteSqlDialect.DEFAULT instead.
  - BUILT_IN_OPERATORS_LIST
```
protected static final java.util.Set<SqlOperator> BUILT_IN_OPERATORS_LIST
```
    Built-in scalar functions and operators common for every dialect.
  - identifierQuoteString
```
private final java.lang.String identifierQuoteString
```
  - identifierEndQuoteString
```
private final java.lang.String identifierEndQuoteString
```
  - identifierEscapedQuote
```
private final java.lang.String identifierEscapedQuote
```
  - databaseProduct
```
private final SqlDialect.DatabaseProduct databaseProduct
```
  - nullCollation
```
protected final NullCollation nullCollation
```
  - dataTypeSystem
```
private final RelDataTypeSystem dataTypeSystem
```
  - HEXITS
```
private static final char[] HEXITS
```
- Constructor Detail
  - SqlDialect
```
@Deprecated
public SqlDialect(SqlDialect.DatabaseProduct databaseProduct,
                  java.lang.String databaseProductName,
                  java.lang.String identifierQuoteString)
```
    Deprecated.
  - SqlDialect
```
@Deprecated
public SqlDialect(SqlDialect.DatabaseProduct databaseProduct,
                  java.lang.String databaseProductName,
                  java.lang.String identifierQuoteString,
                  NullCollation nullCollation)
```
    Deprecated.
    Use SqlDialect(Context)
    
    Creates a SqlDialect.
    
    Parameters:
    
    databaseProduct - Database product; may be UNKNOWN, never null
    
    databaseProductName - Database product name from JDBC driver
    
    identifierQuoteString - String to quote identifiers. Null if quoting is not supported. If "[", close quote is deemed to be "]".
    
    nullCollation - Whether NULL values appear first or last
  - SqlDialect
```
public SqlDialect(SqlDialect.Context context)
```
    Creates a SqlDialect.
    
    Parameters:
    
    context - All the information necessary to create a dialect
- Method Detail
  - create
```
@Deprecated
public static SqlDialect create(java.sql.DatabaseMetaData databaseMetaData)
```
    Deprecated.
    Replaced by SqlDialectFactory
    
    Creates a SqlDialect from a DatabaseMetaData.
    Does not maintain a reference to the DatabaseMetaData -- or, more importantly, to its Connection -- after this call has returned.
    
    Parameters:
    
    databaseMetaData - used to determine which dialect of SQL to generate
  - emptyContext
```
protected static SqlDialect.Context emptyContext()
```
    Creates an empty context. Use EMPTY_CONTEXT if possible.
  - getProduct
```
@Deprecated
public static SqlDialect.DatabaseProduct getProduct(java.lang.String productName,
                                                    java.lang.String productVersion)
```
    Deprecated.
    
    Converts a product name and version (per the JDBC driver) into a product enumeration.
    
    Parameters:
    
    productName - Product name
    
    productVersion - Product version
    
    Returns:
    
    database product
  - getTypeSystem
```
public RelDataTypeSystem getTypeSystem()
```
    Returns the type system implementation for this dialect.
  - quoteIdentifier
```
public java.lang.String quoteIdentifier(java.lang.String val)
```
    Encloses an identifier in quotation marks appropriate for the current SQL dialect.
    For example, quoteIdentifier("emp") yields a string containing "emp" in Oracle, and a string containing [emp] in Access.
    
    Parameters:
    
    val - Identifier to quote
    
    Returns:
    
    Quoted identifier
  - quoteIdentifier
```
public java.lang.StringBuilder quoteIdentifier(java.lang.StringBuilder buf,
                                               java.lang.String val)
```
    Encloses an identifier in quotation marks appropriate for the current SQL dialect, writing the result to a StringBuilder.
    For example, quoteIdentifier("emp") yields a string containing "emp" in Oracle, and a string containing [emp] in Access.
    
    Parameters:
    
    buf - Buffer
    
    val - Identifier to quote
    
    Returns:
    
    The buffer
  - quoteIdentifier
```
public java.lang.StringBuilder quoteIdentifier(java.lang.StringBuilder buf,
                                               java.util.List<java.lang.String> identifiers)
```
    Quotes a multi-part identifier.
    
    Parameters:
    
    buf - Buffer
    
    identifiers - List of parts of the identifier to quote
    
    Returns:
    
    The buffer
  - identifierNeedsToBeQuoted
```
public boolean identifierNeedsToBeQuoted(java.lang.String val)
```
    Returns whether a given identifier needs to be quoted.
  - quoteStringLiteral
```
public java.lang.String quoteStringLiteral(java.lang.String val)
```
    Converts a string into a string literal. For example, can't run becomes 'can''t run'.
  - unparseCall
```
public void unparseCall(SqlWriter writer,
                        SqlCall call,
                        int leftPrec,
                        int rightPrec)
```
  - unparseDateTimeLiteral
```
public void unparseDateTimeLiteral(SqlWriter writer,
                                   SqlAbstractDateTimeLiteral literal,
                                   int leftPrec,
                                   int rightPrec)
```
  - unparseSqlDatetimeArithmetic
```
public void unparseSqlDatetimeArithmetic(SqlWriter writer,
                                         SqlCall call,
                                         SqlKind sqlKind,
                                         int leftPrec,
                                         int rightPrec)
```
  - unparseSqlIntervalQualifier
```
public void unparseSqlIntervalQualifier(SqlWriter writer,
                                        SqlIntervalQualifier qualifier,
                                        RelDataTypeSystem typeSystem)
```
    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).
  - unparseSqlIntervalLiteral
```
public void unparseSqlIntervalLiteral(SqlWriter writer,
                                      SqlIntervalLiteral literal,
                                      int leftPrec,
                                      int rightPrec)
```
    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).
  - containsNonAscii
```
private static boolean containsNonAscii(java.lang.String s)
```
    Returns whether the string contains any characters outside the comfortable 7-bit ASCII range (32 through 127).
    
    Parameters:
    
    s - String
    
    Returns:
    
    Whether string contains any non-7-bit-ASCII characters
  - quoteStringLiteralUnicode
```
public void quoteStringLiteralUnicode(java.lang.StringBuilder buf,
                                      java.lang.String val)
```
    Converts a string into a unicode string literal. For example, can't{tab}run\ becomes u'can''t\0009run\\'.
  - unquoteStringLiteral
```
public java.lang.String unquoteStringLiteral(java.lang.String val)
```
    Converts a string literal back into a string. For example, 'can''t run' becomes can't run.
  - allowsAs
```
protected boolean allowsAs()
```
  - requiresAliasForFromItems
```
protected boolean requiresAliasForFromItems()
```
  - hasImplicitTableAlias
```
public boolean hasImplicitTableAlias()
```
    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.
  - quoteTimestampLiteral
```
public java.lang.String quoteTimestampLiteral(java.sql.Timestamp timestamp)
```
    Converts a timestamp to a SQL timestamp literal, e.g. TIMESTAMP '2009-12-17 12:34:56'.
    Timestamp values do not have a time zone. We therefore interpret them as the number of milliseconds after the UTC epoch, and the formatted value is that time in UTC.
    In particular,
    quoteTimestampLiteral(new Timestamp(0));
    
    returns TIMESTAMP '1970-01-01 00:00:00', regardless of the JVM's time zone.
    
    Parameters:
    
    timestamp - Timestamp
    
    Returns:
    
    SQL timestamp literal
  - getDatabaseProduct
```
@Deprecated
public SqlDialect.DatabaseProduct getDatabaseProduct()
```
    Deprecated.
    To be removed without replacement
    
    Returns the database this dialect belongs to, SqlDialect.DatabaseProduct.UNKNOWN if not known, never null.
    Please be judicious in how you use this method. If you wish to determine whether a dialect has a particular capability or behavior, it is usually better to add a method to SqlDialect and override that method in particular sub-classes of SqlDialect.
    
    Returns:
    
    Database product
  - supportsCharSet
```
public 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`.
  - supportsAggregateFunction
```
public boolean supportsAggregateFunction(SqlKind kind)
```
  - supportsWindowFunctions
```
public boolean supportsWindowFunctions()
```
    Returns whether this dialect supports window functions (OVER clause).
  - supportsFunction
```
public boolean supportsFunction(SqlOperator operator,
                                RelDataType type,
                                java.util.List<RelDataType> paramTypes)
```
    Returns whether this dialect supports a given function or operator. It only applies to built-in scalar functions and operators, since user-defined functions and procedures should be read by JdbcSchema.
  - getCalendarPolicy
```
public SqlDialect.CalendarPolicy getCalendarPolicy()
```
  - getCastSpec
```
public SqlNode getCastSpec(RelDataType type)
```
  - rewriteSingleValueExpr
```
public SqlNode rewriteSingleValueExpr(SqlNode aggCall)
```
    Rewrite SINGLE_VALUE into expression based on database variants E.g. HSQLDB, MYSQL, ORACLE, etc
  - emulateNullDirection
```
public 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.
    
    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
  - emulateNullDirectionWithIsNull
```
protected SqlNode emulateNullDirectionWithIsNull(SqlNode node,
                                                 boolean nullsFirst,
                                                 boolean desc)
```
  - supportsOffsetFetch
```
@Deprecated
public boolean supportsOffsetFetch()
```
    Deprecated.
    This method is no longer used. To change how the dialect unparses offset/fetch, override the unparseOffsetFetch(org.apache.calcite.sql.SqlWriter, org.apache.calcite.sql.SqlNode, org.apache.calcite.sql.SqlNode) method.
    
    Returns whether the dialect supports OFFSET/FETCH clauses introduced by SQL:2008, for instance OFFSET 10 ROWS FETCH NEXT 20 ROWS ONLY. If false, we assume that the dialect supports the alternative syntax LIMIT 20 OFFSET 10.
  - unparseOffsetFetch
```
public void unparseOffsetFetch(SqlWriter writer,
                               SqlNode offset,
                               SqlNode fetch)
```
    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)
    Parameters:
    
    writer - Writer
    
    offset - Number of rows to skip before emitting, or null
    
    fetch - Number of rows to fetch, or null
    
    See Also:
    
    unparseFetchUsingAnsi(SqlWriter, SqlNode, SqlNode), unparseFetchUsingLimit(SqlWriter, SqlNode, SqlNode)
  - unparseFetchUsingAnsi
```
protected final void unparseFetchUsingAnsi(SqlWriter writer,
                                           SqlNode offset,
                                           SqlNode fetch)
```
    Unparses offset/fetch using ANSI standard "OFFSET offset ROWS FETCH NEXT fetch ROWS ONLY" syntax.
  - unparseFetchUsingLimit
```
protected final void unparseFetchUsingLimit(SqlWriter writer,
                                            SqlNode offset,
                                            SqlNode fetch)
```
    Unparses offset/fetch using "LIMIT fetch OFFSET offset" syntax.
  - supportsNestedAggregations
```
public boolean supportsNestedAggregations()
```
    Returns whether the dialect supports nested aggregations, for instance SELECT SUM(SUM(1)) .
  - getNullCollation
```
public NullCollation getNullCollation()
```
    Returns how NULL values are sorted if an ORDER BY item does not contain NULLS ASCENDING or NULLS DESCENDING.
  - defaultNullDirection
```
public RelFieldCollation.NullDirection defaultNullDirection(RelFieldCollation.Direction direction)
```
    Returns whether NULL values are sorted first or last, in this dialect, in an ORDER BY item of a given direction.
  - supportsAliasedValues
```
public boolean supportsAliasedValues()
```
    Returns whether the dialect supports VALUES in a sub-query with and an "AS t(column, ...)" values to define column names.
    Currently, only Oracle does not. For this, we generate "SELECT v0 AS c0, v1 AS c1 ... UNION ALL ...". We may need to refactor this method when we support VALUES for other dialects.

Class SqlDialect

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

LOGGER

EMPTY_CONTEXT

DUMMY

CALCITE

BUILT_IN_OPERATORS_LIST

identifierQuoteString

identifierEndQuoteString

identifierEscapedQuote

databaseProduct

nullCollation

dataTypeSystem

HEXITS

Constructor Detail

SqlDialect

SqlDialect

SqlDialect

Method Detail

create

emptyContext

getProduct

getTypeSystem

quoteIdentifier

quoteIdentifier

quoteIdentifier

identifierNeedsToBeQuoted

quoteStringLiteral

unparseCall

unparseDateTimeLiteral

unparseSqlDatetimeArithmetic

unparseSqlIntervalQualifier

unparseSqlIntervalLiteral

containsNonAscii

quoteStringLiteralUnicode

unquoteStringLiteral

allowsAs

requiresAliasForFromItems

hasImplicitTableAlias

quoteTimestampLiteral

getDatabaseProduct

supportsCharSet

supportsAggregateFunction

supportsWindowFunctions

supportsFunction

getCalendarPolicy

getCastSpec

rewriteSingleValueExpr

emulateNullDirection

emulateNullDirectionWithIsNull

supportsOffsetFetch

unparseOffsetFetch

unparseFetchUsingAnsi

unparseFetchUsingLimit

supportsNestedAggregations

getNullCollation

defaultNullDirection

supportsAliasedValues