abstract class JdbcDialect extends Serializable with Logging
:: DeveloperApi ::
Encapsulates everything (extensions, workarounds, quirks) to handle the
SQL dialect of a certain database or jdbc driver.
Lots of databases define types that aren't explicitly supported
by the JDBC spec. Some JDBC drivers also report inaccurate
information---for instance, BIT(n>
1) being reported as a BIT type is quite
common, even though BIT in JDBC is meant for single-bit values. Also, there
does not appear to be a standard name for an unbounded string or binary
type; we use BLOB and CLOB by default but override with database-specific
alternatives when these are absent or do not behave correctly.
Currently, the only thing done by the dialect is type mapping.
getCatalystType
is used when reading from a JDBC table and getJDBCType
is used when writing to a JDBC table. If getCatalystType
returns null
,
the default type handling is used for the given JDBC type. Similarly,
if getJDBCType
returns (null, None)
, the default type handling is used
for the given Catalyst type.
- Annotations
- @DeveloperApi()
- Source
- JdbcDialects.scala
- Alphabetic
- By Inheritance
- JdbcDialect
- Logging
- Serializable
- AnyRef
- Any
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- Public
- Protected
Instance Constructors
- new JdbcDialect()
Type Members
- implicit class LogStringContext extends AnyRef
- Definition Classes
- Logging
Abstract Value Members
- abstract def canHandle(url: String): Boolean
Check if this dialect instance can handle a certain jdbc url.
Check if this dialect instance can handle a certain jdbc url.
- url
the jdbc url.
- returns
True if the dialect can be applied on the given jdbc url.
- Exceptions thrown
NullPointerException
if the url is null.
Concrete Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##: Int
- Definition Classes
- AnyRef → Any
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- def alterTable(tableName: String, changes: Seq[TableChange], dbMajorVersion: Int): Array[String]
Alter an existing table.
Alter an existing table.
- tableName
The name of the table to be altered.
- changes
Changes to apply to the table.
- returns
The SQL statements to use for altering the table.
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def beforeFetch(connection: Connection, properties: Map[String, String]): Unit
Override connection specific properties to run before a select is made.
Override connection specific properties to run before a select is made. This is in place to allow dialects that need special treatment to optimize behavior.
- connection
The connection object
- properties
The connection properties. This is passed through from the relation.
- def classifyException(e: Throwable, errorClass: String, messageParameters: Map[String, String], description: String): AnalysisException
Gets a dialect exception, classifies it and wraps it by
AnalysisException
.Gets a dialect exception, classifies it and wraps it by
AnalysisException
.- e
The dialect specific exception.
- errorClass
The error class assigned in the case of an unclassified
e
- messageParameters
The message parameters of
errorClass
- description
The error description
- returns
AnalysisException
or its sub-class.
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @IntrinsicCandidate() @native()
- def compileExpression(expr: Expression): Option[String]
Converts V2 expression to String representing a SQL expression.
Converts V2 expression to String representing a SQL expression.
- expr
The V2 expression to be converted.
- returns
Converted value.
- Annotations
- @Since("3.3.0")
- def compileValue(value: Any): Any
Converts value to SQL expression.
Converts value to SQL expression.
- value
The value to be converted.
- returns
Converted value.
- Annotations
- @Since("2.3.0")
- def convertJavaDateToDate(d: Date): Date
Converts an instance of
java.sql.Date
to a customjava.sql.Date
value.Converts an instance of
java.sql.Date
to a customjava.sql.Date
value.- d
the date value returned from JDBC ResultSet getDate method.
- returns
the date value after conversion
- Annotations
- @Since("4.0.0")
- def convertJavaTimestampToTimestamp(t: Timestamp): Timestamp
Converts an instance of
java.sql.Timestamp
to a customjava.sql.Timestamp
value.Converts an instance of
java.sql.Timestamp
to a customjava.sql.Timestamp
value.- t
represents a specific instant in time based on the hybrid calendar which combines Julian and Gregorian calendars.
- returns
the timestamp value to convert to
- Annotations
- @Since("3.5.0")
- Exceptions thrown
IllegalArgumentException
if t is null
- def convertJavaTimestampToTimestampNTZ(t: Timestamp): LocalDateTime
Convert java.sql.Timestamp to a LocalDateTime representing the same wall-clock time as the value stored in a remote database.
Convert java.sql.Timestamp to a LocalDateTime representing the same wall-clock time as the value stored in a remote database. JDBC dialects should override this function to provide implementations that suit their JDBC drivers.
- t
Timestamp returned from JDBC driver getTimestamp method.
- returns
A LocalDateTime representing the same wall clock time as the timestamp in database.
- Annotations
- @Since("3.5.0")
- def convertTimestampNTZToJavaTimestamp(ldt: LocalDateTime): Timestamp
Converts a LocalDateTime representing a TimestampNTZ type to an instance of
java.sql.Timestamp
.Converts a LocalDateTime representing a TimestampNTZ type to an instance of
java.sql.Timestamp
.- ldt
representing a TimestampNTZType.
- returns
A Java Timestamp representing this LocalDateTime.
- Annotations
- @Since("3.5.0")
- def createConnectionFactory(options: JDBCOptions): (Int) => Connection
Returns a factory for creating connections to the given JDBC URL.
Returns a factory for creating connections to the given JDBC URL. In general, creating a connection has nothing to do with JDBC partition id. But sometimes it is needed, such as a database with multiple shard nodes.
- options
- JDBC options that contains url, table and other information.
- returns
The factory method for creating JDBC connections with the RDD partition ID. -1 means the connection is being created at the driver side.
- Annotations
- @Since("3.3.0")
- Exceptions thrown
IllegalArgumentException
if the driver could not open a JDBC connection.
- def createIndex(indexName: String, tableIdent: Identifier, columns: Array[NamedReference], columnsProperties: Map[NamedReference, Map[String, String]], properties: Map[String, String]): String
Build a create index SQL statement.
Build a create index SQL statement.
- indexName
the name of the index to be created
- tableIdent
the table on which index to be created
- columns
the columns on which index to be created
- columnsProperties
the properties of the columns on which index to be created
- properties
the properties of the index to be created
- returns
the SQL statement to use for creating the index.
- def createSchema(statement: Statement, schema: String, comment: String): Unit
Create schema with an optional comment.
Create schema with an optional comment. Empty string means no comment.
- def createTable(statement: Statement, tableName: String, strSchema: String, options: JdbcOptionsInWrite): Unit
Create the table if the table does not exist.
Create the table if the table does not exist. To allow certain options to append when create a new table, which can be table_options or partition_options. E.g., "CREATE TABLE t (name string) ENGINE=InnoDB DEFAULT CHARSET=utf8"
- statement
The Statement object used to execute SQL statements.
- tableName
The name of the table to be created.
- strSchema
The schema of the table to be created.
- options
The JDBC options. It contains the create table option, which can be table_options or partition_options.
- def dropIndex(indexName: String, tableIdent: Identifier): String
Build a drop index SQL statement.
Build a drop index SQL statement.
- indexName
the name of the index to be dropped.
- tableIdent
the table on which index to be dropped.
- returns
the SQL statement to use for dropping the index.
- def dropSchema(schema: String, cascade: Boolean): String
- def dropTable(table: String): String
Build a SQL statement to drop the given table.
Build a SQL statement to drop the given table.
- table
the table name
- returns
The SQL statement to use for drop the table.
- Annotations
- @Since("4.0.0")
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def escapeSql(value: String): String
Escape special characters in SQL string literals.
Escape special characters in SQL string literals.
- value
The string to be escaped.
- returns
Escaped string.
- Attributes
- protected[jdbc]
- Annotations
- @Since("2.3.0")
- def functions: Seq[(String, UnboundFunction)]
List the user-defined functions in jdbc dialect.
List the user-defined functions in jdbc dialect.
- returns
a sequence of tuple from function name to user-defined function.
- def getAddColumnQuery(tableName: String, columnName: String, dataType: String): String
- def getCatalystType(sqlType: Int, typeName: String, size: Int, md: MetadataBuilder): Option[DataType]
Get the custom datatype mapping for the given jdbc meta information.
Get the custom datatype mapping for the given jdbc meta information.
Guidelines for mapping database defined timestamps to Spark SQL timestamps:
- TIMESTAMP WITHOUT TIME ZONE if preferTimestampNTZ -> org.apache.spark.sql.types.TimestampNTZType
- TIMESTAMP WITHOUT TIME ZONE if !preferTimestampNTZ -> org.apache.spark.sql.types.TimestampType(LTZ)
- TIMESTAMP WITH TIME ZONE -> org.apache.spark.sql.types.TimestampType(LTZ)
- TIMESTAMP WITH LOCAL TIME ZONE -> org.apache.spark.sql.types.TimestampType(LTZ)
- If the TIMESTAMP cannot be distinguished by
sqlType
andtypeName
, preferTimestampNTZ is respected for now, but we may need to add another option in the future if necessary.- sqlType
Refers to java.sql.Types constants, or other constants defined by the target database, e.g.
-101
is Oracle's TIMESTAMP WITH TIME ZONE type. This value is returned by java.sql.ResultSetMetaData#getColumnType.- typeName
The column type name used by the database (e.g. "BIGINT UNSIGNED"). This is sometimes used to determine the target data type when
sqlType
is not sufficient if multiple database types are conflated into a single id. This value is returned by java.sql.ResultSetMetaData#getColumnTypeName.- size
The size of the type, e.g. the maximum precision for numeric types, length for character string, etc. This value is returned by java.sql.ResultSetMetaData#getPrecision.
- md
Result metadata associated with this type. This contains additional information from java.sql.ResultSetMetaData or user specified options. -
isTimestampNTZ
: Whether read a TIMESTAMP WITHOUT TIME ZONE value as org.apache.spark.sql.types.TimestampNTZType or not. This is configured byJDBCOptions.preferTimestampNTZ
. -scale
: The length of fractional part java.sql.ResultSetMetaData#getScale- returns
An option the actual DataType (subclasses of org.apache.spark.sql.types.DataType) or None if the default type mapping should be used.
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @IntrinsicCandidate() @native()
- def getDayTimeIntervalAsMicros(daytimeStr: String): Long
Converts a day-time interval string to a long value
micros
.Converts a day-time interval string to a long value
micros
.- daytimeStr
the day-time interval string
- returns
the number of total microseconds in the interval
- Annotations
- @Since("4.0.0")
- Exceptions thrown
IllegalArgumentException
if the input string is invalid
- def getDeleteColumnQuery(tableName: String, columnName: String): String
- def getFullyQualifiedQuotedTableName(ident: Identifier): String
Return the DB-specific quoted and fully qualified table name
Return the DB-specific quoted and fully qualified table name
- Annotations
- @Since("3.5.0")
- def getJDBCType(dt: DataType): Option[JdbcType]
Retrieve the jdbc / sql type for a given datatype.
Retrieve the jdbc / sql type for a given datatype.
- dt
The datatype (e.g. org.apache.spark.sql.types.StringType)
- returns
The new JdbcType if there is an override for this DataType
- def getJdbcSQLQueryBuilder(options: JDBCOptions): JdbcSQLQueryBuilder
Returns the SQL builder for the SELECT statement.
- def getLimitClause(limit: Integer): String
Returns the LIMIT clause for the SELECT statement
- def getOffsetClause(offset: Integer): String
Returns the OFFSET clause for the SELECT statement
- def getRenameColumnQuery(tableName: String, columnName: String, newName: String, dbMajorVersion: Int): String
- def getSchemaCommentQuery(schema: String, comment: String): String
- def getSchemaQuery(table: String): String
The SQL query that should be used to discover the schema of a table.
The SQL query that should be used to discover the schema of a table. It only needs to ensure that the result set has the same schema as the table, such as by calling "SELECT * ...". Dialects can override this method to return a query that works best in a particular database.
- table
The name of the table.
- returns
The SQL query to use for discovering the schema.
- Annotations
- @Since("2.1.0")
- def getTableCommentQuery(table: String, comment: String): String
- def getTableExistsQuery(table: String): String
Get the SQL query that should be used to find if the given table exists.
Get the SQL query that should be used to find if the given table exists. Dialects can override this method to return a query that works best in a particular database.
- table
The name of the table.
- returns
The SQL query to use for checking the table.
- def getTableSample(sample: TableSampleInfo): String
- final def getTimestampType(md: Metadata): DataType
Return TimestampType/TimestampNTZType based on the metadata.
Return TimestampType/TimestampNTZType based on the metadata.
- Attributes
- protected
- def getTruncateQuery(table: String, cascade: Option[Boolean] = isCascadingTruncateTable()): String
The SQL query that should be used to truncate a table.
The SQL query that should be used to truncate a table. Dialects can override this method to return a query that is suitable for a particular database. For PostgreSQL, for instance, a different query is used to prevent "TRUNCATE" affecting other tables.
- table
The table to truncate
- cascade
Whether or not to cascade the truncation
- returns
The SQL query to use for truncating a table
- Annotations
- @Since("2.4.0")
- def getTruncateQuery(table: String): String
The SQL query that should be used to truncate a table.
The SQL query that should be used to truncate a table. Dialects can override this method to return a query that is suitable for a particular database. For PostgreSQL, for instance, a different query is used to prevent "TRUNCATE" affecting other tables.
- table
The table to truncate
- returns
The SQL query to use for truncating a table
- Annotations
- @Since("2.3.0")
- def getUpdateColumnNullabilityQuery(tableName: String, columnName: String, isNullable: Boolean): String
- def getUpdateColumnTypeQuery(tableName: String, columnName: String, newDataType: String): String
- def getYearMonthIntervalAsMonths(yearmonthStr: String): Int
Converts an year-month interval string to an int value
months
.Converts an year-month interval string to an int value
months
.- yearmonthStr
the year-month interval string
- returns
the number of total months in the interval
- Annotations
- @Since("4.0.0")
- Exceptions thrown
IllegalArgumentException
if the input string is invalid
- def hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @IntrinsicCandidate() @native()
- def indexExists(conn: Connection, indexName: String, tableIdent: Identifier, options: JDBCOptions): Boolean
Checks whether an index exists
Checks whether an index exists
- indexName
the name of the index
- tableIdent
the table on which index to be checked
- options
JDBCOptions of the table
- returns
true if the index with
indexName
exists in the table withtableName
, false otherwise
- def initializeLogIfNecessary(isInterpreter: Boolean, silent: Boolean): Boolean
- Attributes
- protected
- Definition Classes
- Logging
- def initializeLogIfNecessary(isInterpreter: Boolean): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def insertIntoTable(table: String, fields: Array[StructField]): String
Returns an Insert SQL statement template for inserting a row into the target table via JDBC conn.
Returns an Insert SQL statement template for inserting a row into the target table via JDBC conn. Use "?" as placeholder for each value to be inserted. E.g.
INSERT INTO t ("name", "age", "gender") VALUES (?, ?, ?)
- table
The name of the table.
- fields
The fields of the row that will be inserted.
- returns
The SQL query to use for insert data into table.
- Annotations
- @Since("4.0.0")
- def isCascadingTruncateTable(): Option[Boolean]
Return Some[true] iff
TRUNCATE TABLE
causes cascading default.Return Some[true] iff
TRUNCATE TABLE
causes cascading default. Some[true] : TRUNCATE TABLE causes cascading. Some[false] : TRUNCATE TABLE does not cause cascading. None: The behavior of TRUNCATE TABLE is unknown (default). - final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- def isSupportedFunction(funcName: String): Boolean
Returns whether the database supports function.
Returns whether the database supports function.
- funcName
Upper-cased function name
- returns
True if the database supports function.
- Annotations
- @Since("3.3.0")
- def isTraceEnabled(): Boolean
- Attributes
- protected
- Definition Classes
- Logging
- def listIndexes(conn: Connection, tableIdent: Identifier, options: JDBCOptions): Array[TableIndex]
Lists all the indexes in this table.
- def listSchemas(conn: Connection, options: JDBCOptions): Array[Array[String]]
Lists all the schemas in this table.
- def log: Logger
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(entry: LogEntry, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(entry: LogEntry): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logDebug(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(entry: LogEntry, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(entry: LogEntry): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logError(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(entry: LogEntry, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(entry: LogEntry): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logInfo(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logName: String
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(entry: LogEntry, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(entry: LogEntry): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logTrace(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(msg: => String, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(entry: LogEntry, throwable: Throwable): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(entry: LogEntry): Unit
- Attributes
- protected
- Definition Classes
- Logging
- def logWarning(msg: => String): Unit
- Attributes
- protected
- Definition Classes
- Logging
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @IntrinsicCandidate() @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @IntrinsicCandidate() @native()
- def quoteIdentifier(colName: String): String
Quotes the identifier.
Quotes the identifier. This is used to put quotes around the identifier in case the column name is a reserved keyword, or in case it contains characters that require quotes (e.g. space).
- def removeSchemaCommentQuery(schema: String): String
- def renameTable(oldTable: Identifier, newTable: Identifier): String
Rename an existing table.
Rename an existing table.
- oldTable
The existing table.
- newTable
New name of the table.
- returns
The SQL statement to use for renaming the table.
- Annotations
- @Since("3.5.0")
- def schemasExists(conn: Connection, options: JDBCOptions, schema: String): Boolean
Check schema exists or not.
- def supportsLimit: Boolean
Returns ture if dialect supports LIMIT clause.
Returns ture if dialect supports LIMIT clause.
Note: Some build-in dialect supports LIMIT clause with some trick, please see:
OracleDialect.OracleSQLQueryBuilder
andMsSqlServerDialect.MsSqlServerSQLQueryBuilder
. - def supportsOffset: Boolean
Returns ture if dialect supports OFFSET clause.
Returns ture if dialect supports OFFSET clause.
Note: Some build-in dialect supports OFFSET clause with some trick, please see:
OracleDialect.OracleSQLQueryBuilder
andMySQLDialect.MySQLSQLQueryBuilder
. - def supportsTableSample: Boolean
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- AnyRef → Any
- def updateExtraColumnMeta(conn: Connection, rsmd: ResultSetMetaData, columnIdx: Int, metadata: MetadataBuilder): Unit
Get extra column metadata for the given column.
Get extra column metadata for the given column.
- conn
The connection currently connection being used.
- rsmd
The metadata of the current result set.
- columnIdx
The index of the column.
- metadata
The metadata builder to store the extra column information.
- Annotations
- @Since("4.0.0")
- final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()
- final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- def withLogContext(context: HashMap[String, String])(body: => Unit): Unit
- Attributes
- protected
- Definition Classes
- Logging
Deprecated Value Members
- def classifyException(message: String, e: Throwable): AnalysisException
Gets a dialect exception, classifies it and wraps it by
AnalysisException
.Gets a dialect exception, classifies it and wraps it by
AnalysisException
.- message
The error message to be placed to the returned exception.
- e
The dialect specific exception.
- returns
AnalysisException
or its sub-class.
- Annotations
- @deprecated
- Deprecated
(Since version 4.0.0) Please override the classifyException method with an error class
- def compileAggregate(aggFunction: AggregateFunc): Option[String]
Converts aggregate function to String representing a SQL expression.
Converts aggregate function to String representing a SQL expression.
- aggFunction
The aggregate function to be converted.
- returns
Converted value.
- Annotations
- @Since("3.3.0") @deprecated
- Deprecated
(Since version 3.4.0) use org.apache.spark.sql.jdbc.JdbcDialect.compileExpression instead.
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable]) @Deprecated
- Deprecated
(Since version 9)
- def renameTable(oldTable: String, newTable: String): String
Rename an existing table.
Rename an existing table.
- oldTable
The existing table.
- newTable
New name of the table.
- returns
The SQL statement to use for renaming the table.
- Annotations
- @deprecated
- Deprecated
(Since version 3.5.0) Please override renameTable method with identifiers