com.gpudb.protocol

Class GetRecordsByColumnRequest

java.lang.Object

com.gpudb.protocol.GetRecordsByColumnRequest

All Implemented Interfaces:

org.apache.avro.generic.GenericContainer, org.apache.avro.generic.IndexedRecord

public class GetRecordsByColumnRequest
extends Object
implements org.apache.avro.generic.IndexedRecord

A set of parameters for GPUdb.getRecordsByColumnRaw(GetRecordsByColumnRequest).

For a given table, retrieves the values from the requested column(s). Maps of column name to the array of values as well as the column data type are returned. This endpoint supports pagination with the offset and limit parameters.

Window functions, which can perform operations like moving averages, are available through this endpoint as well as GPUdb.createProjection(CreateProjectionRequest).

When using pagination, if the table (or the underlying table in the case of a view) is modified (records are inserted, updated, or deleted) during a call to the endpoint, the records or values retrieved may differ between calls based on the type of the update, e.g., the contiguity across pages cannot be relied upon.

If tableName is empty, selection is performed against a single-row virtual table. This can be useful in executing temporal (NOW()), identity (USER()), or constant-based functions (GEODIST(-77.11, 38.88, -71.06, 42.36)).

The response is returned as a dynamic schema. For details see: dynamic schemas documentation.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	GetRecordsByColumnRequest.Encoding Specifies the encoding for returned records; either 'binary' or 'json'.
static class	GetRecordsByColumnRequest.Options EXPRESSION: Optional filter expression to apply to the table.

Constructor Summary

Constructors

Constructor and Description
GetRecordsByColumnRequest() Constructs a GetRecordsByColumnRequest object with default parameters.
GetRecordsByColumnRequest(String tableName, List<String> columnNames, long offset, long limit, Map<String,String> options) Constructs a GetRecordsByColumnRequest object with the specified parameters.
GetRecordsByColumnRequest(String tableName, List<String> columnNames, long offset, long limit, String encoding, Map<String,String> options) Constructs a GetRecordsByColumnRequest object with the specified parameters.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
Object	get(int index) This method supports the Avro framework and is not intended to be called directly by the user.
static org.apache.avro.Schema	getClassSchema() This method supports the Avro framework and is not intended to be called directly by the user.
List<String>	getColumnNames()
String	getEncoding()
long	getLimit()
long	getOffset()
Map<String,String>	getOptions()
org.apache.avro.Schema	getSchema() This method supports the Avro framework and is not intended to be called directly by the user.
String	getTableName()
int	hashCode()
void	put(int index, Object value) This method supports the Avro framework and is not intended to be called directly by the user.
GetRecordsByColumnRequest	setColumnNames(List<String> columnNames)
GetRecordsByColumnRequest	setEncoding(String encoding)
GetRecordsByColumnRequest	setLimit(long limit)
GetRecordsByColumnRequest	setOffset(long offset)
GetRecordsByColumnRequest	setOptions(Map<String,String> options)
GetRecordsByColumnRequest	setTableName(String tableName)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

GetRecordsByColumnRequest

public GetRecordsByColumnRequest()

Constructs a GetRecordsByColumnRequest object with default parameters.

GetRecordsByColumnRequest

public GetRecordsByColumnRequest(String tableName,
                                 List<String> columnNames,
                                 long offset,
                                 long limit,
                                 Map<String,String> options)

Constructs a GetRecordsByColumnRequest object with the specified parameters.

Parameters:

tableName - Name of the table on which this operation will be performed. An empty table name retrieves one record from a single-row virtual table, where columns specified should be constants or constant expressions. The table cannot be a parent set.

columnNames - The list of column values to retrieve.

offset - A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The default value is 0.The minimum allowed value is 0. The maximum allowed value is MAX_INT.

limit - A positive integer indicating the maximum number of results to be returned, or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned. The number of records returned will never exceed the server's own limit, defined by the max_get_records_size parameter in the server configuration. Use hasMoreRecords to see if more records exist in the result to be fetched, and offset & limit to request subsequent pages of results. The default value is -9999.

options -

• EXPRESSION: Optional filter expression to apply to the table.
• SORT_BY: Optional column that the data should be sorted by. Used in conjunction with sort_order. The order_by option can be used in lieu of sort_by / sort_order. The default value is ''.
• SORT_ORDER: String indicating how the returned values should be sorted - ascending or descending. If sort_order is provided, sort_by has to be provided. Supported values:
  • ASCENDING
  • DESCENDING
  The default value is ASCENDING.
• ORDER_BY: Comma-separated list of the columns to be sorted by as well as the sort direction, e.g., 'timestamp asc, x desc'. The default value is ''.
• CONVERT_WKTS_TO_WKBS: If true, then WKT string columns will be returned as WKB bytes. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.

The default value is an empty Map.

GetRecordsByColumnRequest

public GetRecordsByColumnRequest(String tableName,
                                 List<String> columnNames,
                                 long offset,
                                 long limit,
                                 String encoding,
                                 Map<String,String> options)

Constructs a GetRecordsByColumnRequest object with the specified parameters.

Parameters:

tableName - Name of the table on which this operation will be performed. An empty table name retrieves one record from a single-row virtual table, where columns specified should be constants or constant expressions. The table cannot be a parent set.

columnNames - The list of column values to retrieve.

offset - A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The default value is 0.The minimum allowed value is 0. The maximum allowed value is MAX_INT.

limit - A positive integer indicating the maximum number of results to be returned, or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned. The number of records returned will never exceed the server's own limit, defined by the max_get_records_size parameter in the server configuration. Use hasMoreRecords to see if more records exist in the result to be fetched, and offset & limit to request subsequent pages of results. The default value is -9999.

encoding - Specifies the encoding for returned records; either 'binary' or 'json'. Supported values:

• BINARY
• JSON

The default value is BINARY.

options -

• EXPRESSION: Optional filter expression to apply to the table.
• SORT_BY: Optional column that the data should be sorted by. Used in conjunction with sort_order. The order_by option can be used in lieu of sort_by / sort_order. The default value is ''.
• SORT_ORDER: String indicating how the returned values should be sorted - ascending or descending. If sort_order is provided, sort_by has to be provided. Supported values:
  • ASCENDING
  • DESCENDING
  The default value is ASCENDING.
• ORDER_BY: Comma-separated list of the columns to be sorted by as well as the sort direction, e.g., 'timestamp asc, x desc'. The default value is ''.
• CONVERT_WKTS_TO_WKBS: If true, then WKT string columns will be returned as WKB bytes. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.

The default value is an empty Map.

Method Detail

getClassSchema

public static org.apache.avro.Schema getClassSchema()

This method supports the Avro framework and is not intended to be called directly by the user.

Returns:

the schema for the class.

getTableName

public String getTableName()

Returns:

Name of the table on which this operation will be performed. An empty table name retrieves one record from a single-row virtual table, where columns specified should be constants or constant expressions. The table cannot be a parent set.

setTableName

public GetRecordsByColumnRequest setTableName(String tableName)

Parameters:

tableName - Name of the table on which this operation will be performed. An empty table name retrieves one record from a single-row virtual table, where columns specified should be constants or constant expressions. The table cannot be a parent set.

Returns:

this to mimic the builder pattern.

getColumnNames

public List<String> getColumnNames()

Returns:

The list of column values to retrieve.

setColumnNames

public GetRecordsByColumnRequest setColumnNames(List<String> columnNames)

Parameters:

columnNames - The list of column values to retrieve.

Returns:

this to mimic the builder pattern.

getOffset

public long getOffset()

Returns:

A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The default value is 0.The minimum allowed value is 0. The maximum allowed value is MAX_INT.

setOffset

public GetRecordsByColumnRequest setOffset(long offset)

Parameters:

offset - A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The default value is 0.The minimum allowed value is 0. The maximum allowed value is MAX_INT.

Returns:

this to mimic the builder pattern.

getLimit

public long getLimit()

Returns:

A positive integer indicating the maximum number of results to be returned, or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned. The number of records returned will never exceed the server's own limit, defined by the max_get_records_size parameter in the server configuration. Use hasMoreRecords to see if more records exist in the result to be fetched, and offset & limit to request subsequent pages of results. The default value is -9999.

setLimit

public GetRecordsByColumnRequest setLimit(long limit)

Parameters:

limit - A positive integer indicating the maximum number of results to be returned, or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned. The number of records returned will never exceed the server's own limit, defined by the max_get_records_size parameter in the server configuration. Use hasMoreRecords to see if more records exist in the result to be fetched, and offset & limit to request subsequent pages of results. The default value is -9999.

Returns:

this to mimic the builder pattern.

getEncoding

public String getEncoding()

Returns:

Specifies the encoding for returned records; either 'binary' or 'json'. Supported values:

• BINARY
• JSON

The default value is BINARY.

setEncoding

public GetRecordsByColumnRequest setEncoding(String encoding)

Parameters:

encoding - Specifies the encoding for returned records; either 'binary' or 'json'. Supported values:

• BINARY
• JSON

The default value is BINARY.

Returns:

this to mimic the builder pattern.

getOptions

public Map<String,String> getOptions()

Returns:

• EXPRESSION: Optional filter expression to apply to the table.
• SORT_BY: Optional column that the data should be sorted by. Used in conjunction with sort_order. The order_by option can be used in lieu of sort_by / sort_order. The default value is ''.
• SORT_ORDER: String indicating how the returned values should be sorted - ascending or descending. If sort_order is provided, sort_by has to be provided. Supported values:
  • ASCENDING
  • DESCENDING
  The default value is ASCENDING.
• ORDER_BY: Comma-separated list of the columns to be sorted by as well as the sort direction, e.g., 'timestamp asc, x desc'. The default value is ''.
• CONVERT_WKTS_TO_WKBS: If true, then WKT string columns will be returned as WKB bytes. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.

The default value is an empty Map.

setOptions

public GetRecordsByColumnRequest setOptions(Map<String,String> options)

Parameters:

options -

• EXPRESSION: Optional filter expression to apply to the table.
• SORT_BY: Optional column that the data should be sorted by. Used in conjunction with sort_order. The order_by option can be used in lieu of sort_by / sort_order. The default value is ''.
• SORT_ORDER: String indicating how the returned values should be sorted - ascending or descending. If sort_order is provided, sort_by has to be provided. Supported values:
  • ASCENDING
  • DESCENDING
  The default value is ASCENDING.
• ORDER_BY: Comma-separated list of the columns to be sorted by as well as the sort direction, e.g., 'timestamp asc, x desc'. The default value is ''.
• CONVERT_WKTS_TO_WKBS: If true, then WKT string columns will be returned as WKB bytes. Supported values:
  • TRUE
  • FALSE
  The default value is FALSE.

The default value is an empty Map.

Returns:

this to mimic the builder pattern.

getSchema

public org.apache.avro.Schema getSchema()

This method supports the Avro framework and is not intended to be called directly by the user.

Specified by:

getSchema in interface org.apache.avro.generic.GenericContainer

Returns:

the schema object describing this class.

get

public Object get(int index)

This method supports the Avro framework and is not intended to be called directly by the user.

Specified by:

get in interface org.apache.avro.generic.IndexedRecord

Parameters:

index - the position of the field to get

Returns:

value of the field with the given index.

Throws:

IndexOutOfBoundsException

put

public void put(int index,
                Object value)

This method supports the Avro framework and is not intended to be called directly by the user.

Specified by:

put in interface org.apache.avro.generic.IndexedRecord

Parameters:

index - the position of the field to set

value - the value to set

Throws:

IndexOutOfBoundsException

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