Package org.pgcodekeeper.core.schema.pg

Class PgStatistics

java.lang.Object

org.pgcodekeeper.core.schema.PgStatement

org.pgcodekeeper.core.schema.AbstractStatistics

org.pgcodekeeper.core.schema.pg.PgStatistics

All Implemented Interfaces:

IHashable, ISearchPath, IStatement

public final class PgStatistics
extends AbstractStatistics

PostgreSQL extended statistics implementation. Extended statistics collect additional information about column correlations and distributions to improve query planning for multi-column predicates.

Field Summary

Fields inherited from class org.pgcodekeeper.core.schema.PgStatement

GO

Constructor Summary

Constructors

Constructor	Description
PgStatistics(String name)	Creates a new PostgreSQL statistics object.

Method Summary

Modifier and Type	Method	Description
void	addExpr(String expression)	Adds a column expression for statistics collection.
void	addKind(String kind)	Adds a statistics kind (ndistinct, dependencies, mcv, etc.).
ObjectState	appendAlterSQL(PgStatement newCondition, SQLScript script)	Fill script with object changes and return change type
boolean	compare(PgStatement obj)	This method does not account for nested child PgStatements.
void	computeHash(Hasher hasher)	Computes the hash of the implementing object using the provided hasher.
void	getCreationSQL(SQLScript script)	Generates the SQL statements needed to create this database object.
String	getForeignSchema()
String	getForeignTable()
void	setForeignSchema(String foreignSchema)
void	setForeignTable(String foreignTable)
void	setStatistics(int statistics)

Methods inherited from class org.pgcodekeeper.core.schema.AbstractStatistics

getContainingSchema, getStatementType, shallowCopy

Methods inherited from class org.pgcodekeeper.core.schema.PgStatement

addAllDeps, addDep, addPrivilege, appendAlterComments, appendComments, appendOwnerSQL, canDrop, canDropBeforeCreate, checkComments, clearPrivileges, compareChildren, deepCopy, equals, getAuthor, getBareName, getChildren, getComment, getDbType, getDeps, getDescendants, getDropSQL, getDropSQL, getLibName, getLocation, getName, getObjectState, getObjectState, getOwner, getParent, getPrivileges, getQualifiedName, getSQL, getTwin, getTypeName, hasChildren, hashCode, isLib, isOwned, isSubElement, setAuthor, setComment, setLibName, setLocation, setOwner, setParent, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.pgcodekeeper.core.schema.ISearchPath

getDatabase, getSchemaName

Methods inherited from interface org.pgcodekeeper.core.schema.IStatement

getBareName, getComment, getName, getParent, getQualifiedName

Constructor Details

PgStatistics

public PgStatistics(String name)

Creates a new PostgreSQL statistics object.

Parameters:

name - statistics object name

Method Details

getCreationSQL

public void getCreationSQL(SQLScript script)

Description copied from class: PgStatement

Generates the SQL statements needed to create this database object. This is an abstract method that must be implemented by subclasses to provide the specific CREATE SQL for each object type.

Specified by:

getCreationSQL in class PgStatement

Parameters:

script - the SQL script to append creation statements to

appendAlterSQL

public ObjectState appendAlterSQL(PgStatement newCondition,
 SQLScript script)

Description copied from class: PgStatement

Fill script with object changes and return change type

Specified by:

appendAlterSQL in class PgStatement

Parameters:

newCondition - new object state

script - script to collect changes

Returns:

object change type

setForeignSchema

public void setForeignSchema(String foreignSchema)

setForeignTable

public void setForeignTable(String foreignTable)

setStatistics

public void setStatistics(int statistics)

addKind

public void addKind(String kind)

Adds a statistics kind (ndistinct, dependencies, mcv, etc.).

Parameters:

kind - statistics type to collect

addExpr

public void addExpr(String expression)

Adds a column expression for statistics collection.

Parameters:

expression - column name or expression

getForeignSchema

public String getForeignSchema()

getForeignTable

public String getForeignTable()

compare

public boolean compare(PgStatement obj)

Description copied from class: PgStatement

This method does not account for nested child PgStatements. Shallow version of PgStatement.equals(Object)

Overrides:

compare in class PgStatement

computeHash

public void computeHash(Hasher hasher)

Description copied from interface: IHashable

Computes the hash of the implementing object using the provided hasher. The implementation should call appropriate put methods on the hasher for all fields that should contribute to the hash value.

Parameters:

hasher - the hasher instance to use for hash computation