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NdbDictionary

None

This class represents an index on anNDB Cluster table column. It is a descendant of theNdbDictionary class, using theObject class.

If you create or change indexes using the NDB API, these modifications cannot be seen by MySQL. The only exception to this is usingIndex::setName() to rename the index.

The following table lists the public methods ofIndex and the purpose or use of each method:

Index defines one public type, theType type.

This is used to create an new instance ofIndex.

Indexes created using the NDB API cannot be seen by the MySQL Server.

Index    (      const char*name = ""    )

The name of the new index. It is possible to create an index without a name, and then assign a name to it later usingsetName(). SeeIndex::setName().

A new instance ofIndex.

The destructor (~Index()) is supplied as a virtual method.

This method may be used to add a column to an index.

The order of the columns matches the order in which they are added to the index. However, this matters only with ordered indexes.

void addColumn    (      const Column&c    )

A referencec to the column which is to be added to the index.

None.

This method works in the same way asaddColumn(), except that it takes the name of the column as a parameter. SeeIndex::getColumn().

void addColumnName    (      const char*name    )

Thename of the column to be added to the index, as a constant character pointer.

None.

This method is used to add several column names to an index definition at one time.

As with theaddColumn() andaddColumnName() methods, the indexes are numbered in the order in which they were added. This normally matters only for ordered indexes.

void addColumnNames    (      unsignednoOfNames,      const char**names    )

This method takes two parameters, listed here:

None.

This method retrieves the column at the specified position within the index.

const Column* getColumn    (      unsignedno    ) const

The ordinal position numberno of the column, as an unsigned integer. Use thegetNoOfColumns() method to determine how many columns make up the index—seeIndex::getNoOfColumns(), for details.

The column having positionno in the index, as a pointer to an instance ofColumn. SeeSection 2.3.1, “The Column Class”.

Use this method to determine whether logging to disk has been enabled for the index.

Indexes which are not logged are rebuilt when the cluster is started or restarted.

Ordered indexes currently do not support logging to disk; they are rebuilt each time the cluster is started. (This includes restarts.)

bool getLogging    (      void    ) const

None.

A Boolean value:

This method is used to obtain the name of an index.

const char* getName    (      void    ) const

None.

The name of the index, as a constant character pointer.

This method is used to obtain the number of columns making up the index.

unsigned getNoOfColumns    (      void    ) const

None.

An unsigned integer representing the number of columns in the index.

This method gets the object status of the index.

virtual Object::Status getObjectStatus    (      void    ) const

None.

AStatus value; seeObject::Status, for more information.

This method gets the object version of the index (seeNDB Schema Object Versions).

virtual int getObjectVersion    (      void    ) const

None.

The object version for the index, as an integer.

This method is used to obtain the object ID of the index.

virtual int getObjectId    (      void    ) const

None.

The object ID, as an integer.

This method can be used to obtain the name of the table to which the index belongs.

const char* getTable    (      void    ) const

None.

The name of the table, as a constant character pointer.

This method can be used to find the type of index.

Type getType    (      void    ) const

None.

An index type. SeeIndex::Type, for possible values.

This method is used to enable or disable logging of the index to disk.

void setLogging    (      boolenable    )

setLogging() takes a single Boolean parameterenable. Ifenable istrue, then logging is enabled for the index; if false, then logging of this index is disabled.

None.

This method sets the name of the index.

This is the onlyIndex::set*() method whose result is visible to a MySQL Server.

void setName    (      const char*name    )

The desiredname for the index, as a constant character pointer.

None.

This method sets the table that is to be indexed. The table is referenced by name.

void setTable    (      const char*name    )

Thename of the table to be indexed, as a constant character pointer.

None.

This method is used to set the index type.

void setType    (      Typetype    )

Thetype of index. For possible values, seeIndex::Type.

None.

This is an enumerated type which describes the sort of column index represented by a given instance ofIndex.

Do not confuse this enumerated type withObject::Type, or withColumn::Type.

Possible values are shown, along with descriptions, in the following table: