org.apache.hadoop.hive.ql.stats.jdbc

Class JDBCStatsUtils

java.lang.Object

org.apache.hadoop.hive.ql.stats.jdbc.JDBCStatsUtils

public class JDBCStatsUtils
extends Object

Constructor Summary

Constructors

Constructor and Description
JDBCStatsUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static String	getAlterIdColumn() Prepares ALTER TABLE query
static String	getBasicStat() Returns the basic type of the supported statistics.
static String	getCreate(String comment) Prepares CREATE TABLE query
static String	getDeleteAggr(String rowID, String comment) Prepares DELETE statement for cleanup.
static String	getIdColumnName() Returns the name of the column storing the key for statistics.
static String	getInsert(String comment) Prepares INSERT statement for statistic publishing.
static String	getSelectAggr(String statType, String comment) Prepares SELECT query for statistics aggregation.
static String	getStatColumnName(String statType) Returns the column where the statistics for the given type are stored.
static String	getStatTableName()
static List<String>	getSupportedStatistics() Returns the set of supported statistics
static String	getTimestampColumnName()
static String	getUpdate(String comment) Prepares UPDATE statement issued when updating existing statistics
static boolean	isValidStatistic(String statType) Check if a particular statistic type is supported
static boolean	isValidStatisticSet(Collection<String> stats) Check if the set to be published is within the supported statistics.
static void	validateRowId(String rowId) Make sure the row ID fits into the row ID column in the table.

Methods inherited from class java.lang.Object

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

Constructor Detail

JDBCStatsUtils

public JDBCStatsUtils()

Method Detail

getSupportedStatistics

public static List<String> getSupportedStatistics()

Returns the set of supported statistics

isValidStatisticSet

public static boolean isValidStatisticSet(Collection<String> stats)

Check if the set to be published is within the supported statistics. It must also contain at least the basic statistics (used for comparison)

Parameters:

stats - - stats to be published

Returns:

true if is a valid statistic set, false otherwise

isValidStatistic

public static boolean isValidStatistic(String statType)

Check if a particular statistic type is supported

Parameters:

statType - - statistic to be published

Returns:

true if statType is supported, false otherwise

getIdColumnName

public static String getIdColumnName()

Returns the name of the column storing the key for statistics.

getTimestampColumnName

public static String getTimestampColumnName()

getStatTableName

public static String getStatTableName()

getStatColumnName

public static String getStatColumnName(String statType)

Returns the column where the statistics for the given type are stored.

Parameters:

statType - - supported statistic.

Returns:

column name for the given statistic.

getBasicStat

public static String getBasicStat()

Returns the basic type of the supported statistics. It is used to determine which statistics are fresher.

getCreate

public static String getCreate(String comment)

Prepares CREATE TABLE query

getAlterIdColumn

public static String getAlterIdColumn()

Prepares ALTER TABLE query

getUpdate

public static String getUpdate(String comment)

Prepares UPDATE statement issued when updating existing statistics

getInsert

public static String getInsert(String comment)

Prepares INSERT statement for statistic publishing.

getSelectAggr

public static String getSelectAggr(String statType,
                   String comment)

Prepares SELECT query for statistics aggregation.

Parameters:

statType - - statistic type to be aggregated.

comment -

Returns:

aggregated value for the given statistic

getDeleteAggr

public static String getDeleteAggr(String rowID,
                   String comment)

Prepares DELETE statement for cleanup.

validateRowId

public static void validateRowId(String rowId)

Make sure the row ID fits into the row ID column in the table.