com.gpudb.protocol

Class UpdateRecordsRequest<T>

java.lang.Object

com.gpudb.protocol.UpdateRecordsRequest<T>

Type Parameters:

T - The type of object being processed.

public class UpdateRecordsRequest<T>
extends Object

A set of parameters for GPUdb.updateRecords(UpdateRecordsRequest).

Runs multiple predicate-based updates in a single call. With the list of given expressions, any matching record's column values will be updated as provided in newValuesMaps. There is also an optional 'upsert' capability where if a particular predicate doesn't match any existing record, then a new record can be inserted.

Note that this operation can only be run on an original table and not on a collection or a result view.

This operation can update primary key values. By default only 'pure primary key' predicates are allowed when updating primary key values. If the primary key for a table is the column 'attr1', then the operation will only accept predicates of the form: "attr1 == 'foo'" if the attr1 column is being updated. For a composite primary key (e.g. columns 'attr1' and 'attr2') then this operation will only accept predicates of the form: "(attr1 == 'foo') and (attr2 == 'bar')". Meaning, all primary key columns must appear in an equality predicate in the expressions. Furthermore each 'pure primary key' predicate must be unique within a given request. These restrictions can be removed by utilizing some available options through options.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UpdateRecordsRequest.Options Optional parameters.

Constructor Summary

Constructors

Constructor and Description
UpdateRecordsRequest() Constructs an UpdateRecordsRequest object with default parameters.
UpdateRecordsRequest(String tableName, List<String> expressions, List<Map<String,String>> newValuesMaps, List<T> data, Map<String,String> options) Constructs an UpdateRecordsRequest object with the specified parameters.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object obj)
List<T>	getData()
List<String>	getExpressions()
List<Map<String,String>>	getNewValuesMaps()
Map<String,String>	getOptions()
String	getTableName()
int	hashCode()
UpdateRecordsRequest<T>	setData(List<T> data)
UpdateRecordsRequest<T>	setExpressions(List<String> expressions)
UpdateRecordsRequest<T>	setNewValuesMaps(List<Map<String,String>> newValuesMaps)
UpdateRecordsRequest<T>	setOptions(Map<String,String> options)
UpdateRecordsRequest<T>	setTableName(String tableName)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

UpdateRecordsRequest

public UpdateRecordsRequest()

Constructs an UpdateRecordsRequest object with default parameters.

UpdateRecordsRequest

public UpdateRecordsRequest(String tableName,
                    List<String> expressions,
                    List<Map<String,String>> newValuesMaps,
                    List<T> data,
                    Map<String,String> options)

Constructs an UpdateRecordsRequest object with the specified parameters.

Parameters:

tableName - Table to be updated. Must be a currently existing table and not a collection or view.

expressions - A list of the actual predicates, one for each update; format should follow the guidelines here.

newValuesMaps - List of new values for the matching records. Each element is a map with (key, value) pairs where the keys are the names of the columns whose values are to be updated; the values are the new values. The number of elements in the list should match the length of expressions.

data - An *optional* list of new binary-avro encoded records to insert, one for each update. If one of expressions does not yield a matching record to be updated, then the corresponding element from this list will be added to the table.

options - Optional parameters.

• GLOBAL_EXPRESSION: An optional global expression to reduce the search space of the predicates listed in expressions.
• BYPASS_SAFETY_CHECKS: When set to 'true', all predicates are available for primary key updates. Keep in mind that it is possible to destroy data in this case, since a single predicate may match multiple objects (potentially all of records of a table), and then updating all of those records to have the same primary key will, due to the primary key uniqueness constraints, effectively delete all but one of those updated records. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• UPDATE_ON_EXISTING_PK: Can be used to customize behavior when the updated primary key value already exists, as described in GPUdb.insertRecords(InsertRecordsRequest). Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• RECORD_ID: ID of a single record to be updated (returned in the call to GPUdb.insertRecords(InsertRecordsRequest) or GPUdb.getRecordsFromCollection(Object, GetRecordsFromCollectionRequest)).

Method Detail

getTableName

public String getTableName()

Returns:

Table to be updated. Must be a currently existing table and not a collection or view.

setTableName

public UpdateRecordsRequest<T> setTableName(String tableName)

Parameters:

tableName - Table to be updated. Must be a currently existing table and not a collection or view.

Returns:

this to mimic the builder pattern.

getExpressions

public List<String> getExpressions()

Returns:

A list of the actual predicates, one for each update; format should follow the guidelines here.

setExpressions

public UpdateRecordsRequest<T> setExpressions(List<String> expressions)

Parameters:

expressions - A list of the actual predicates, one for each update; format should follow the guidelines here.

Returns:

this to mimic the builder pattern.

getNewValuesMaps

public List<Map<String,String>> getNewValuesMaps()

Returns:

List of new values for the matching records. Each element is a map with (key, value) pairs where the keys are the names of the columns whose values are to be updated; the values are the new values. The number of elements in the list should match the length of expressions.

setNewValuesMaps

public UpdateRecordsRequest<T> setNewValuesMaps(List<Map<String,String>> newValuesMaps)

Parameters:

newValuesMaps - List of new values for the matching records. Each element is a map with (key, value) pairs where the keys are the names of the columns whose values are to be updated; the values are the new values. The number of elements in the list should match the length of expressions.

Returns:

this to mimic the builder pattern.

getData

public List<T> getData()

Returns:

An *optional* list of new binary-avro encoded records to insert, one for each update. If one of expressions does not yield a matching record to be updated, then the corresponding element from this list will be added to the table.

setData

public UpdateRecordsRequest<T> setData(List<T> data)

Parameters:

data - An *optional* list of new binary-avro encoded records to insert, one for each update. If one of expressions does not yield a matching record to be updated, then the corresponding element from this list will be added to the table.

Returns:

this to mimic the builder pattern.

getOptions

public Map<String,String> getOptions()

Returns:

Optional parameters.

• GLOBAL_EXPRESSION: An optional global expression to reduce the search space of the predicates listed in expressions.
• BYPASS_SAFETY_CHECKS: When set to 'true', all predicates are available for primary key updates. Keep in mind that it is possible to destroy data in this case, since a single predicate may match multiple objects (potentially all of records of a table), and then updating all of those records to have the same primary key will, due to the primary key uniqueness constraints, effectively delete all but one of those updated records. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• UPDATE_ON_EXISTING_PK: Can be used to customize behavior when the updated primary key value already exists, as described in GPUdb.insertRecords(InsertRecordsRequest). Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• RECORD_ID: ID of a single record to be updated (returned in the call to GPUdb.insertRecords(InsertRecordsRequest) or GPUdb.getRecordsFromCollection(Object, GetRecordsFromCollectionRequest)).

setOptions

public UpdateRecordsRequest<T> setOptions(Map<String,String> options)

Parameters:

options - Optional parameters.

• GLOBAL_EXPRESSION: An optional global expression to reduce the search space of the predicates listed in expressions.
• BYPASS_SAFETY_CHECKS: When set to 'true', all predicates are available for primary key updates. Keep in mind that it is possible to destroy data in this case, since a single predicate may match multiple objects (potentially all of records of a table), and then updating all of those records to have the same primary key will, due to the primary key uniqueness constraints, effectively delete all but one of those updated records. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• UPDATE_ON_EXISTING_PK: Can be used to customize behavior when the updated primary key value already exists, as described in GPUdb.insertRecords(InsertRecordsRequest). Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.
• RECORD_ID: ID of a single record to be updated (returned in the call to GPUdb.insertRecords(InsertRecordsRequest) or GPUdb.getRecordsFromCollection(Object, GetRecordsFromCollectionRequest)).

Returns:

this to mimic the builder pattern.

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object