public class SimpleJsonVTI extends VTITemplate
This is a table function which turns a JSON array into a relational ResultSet. This table function relies on the JSON.simple JSONArray class found at https://code.google.com/p/json-simple/. Each object in the array is turned into a row. The shape of the row is declared by the CREATE FUNCTION ddl and the shape corresponds to the key names found in the row objects. Provided that the values in those objects have the expected type, the following ResultSet accessors can be called:
This table function relies on the JSONArray type loaded by the simpleJson optional tool. This table function can be combined with other JSONArray-creating functions provided by that tool.
Here's an example of how to use this VTI on a JSON document read across the network using the readArrayFromURL function provided by the simpleJson tool:
call syscs_util.syscs_register_tool( 'simpleJson', true ); create function thermostatReadings( jsonDocument JSONArray ) returns table ( "id" int, "temperature" float, "fanOn" boolean ) language java parameter style derby_jdbc_result_set contains sql external name 'org.apache.derby.optional.api.SimpleJsonVTI.readArray'; select * from table ( thermostatReadings ( readArrayFromURL( 'https://thermostat.feed.org', 'UTF-8' ) ) ) t;
That returns a table like this:
id |temperature |fanOn ------------------------------------------ 1 |70.3 |true 2 |65.5 |false
Here's an example of how to use this VTI on a JSON document string with the assistance of the readArrayFromString function provided by the simpleJson tool:
select * from table ( thermostatReadings ( readArrayFromString ( '[ { "id": 1, "temperature": 70.3, "fanOn": true }, { "id": 2, "temperature": 65.5, "fanOn": false } ]' ) ) ) t;
VTITemplate.ColumnDescriptor
Modifier and Type | Method and Description |
---|---|
void |
clearWarnings() |
void |
close() |
java.math.BigDecimal |
getBigDecimal(int columnIndex) |
boolean |
getBoolean(int columnIndex) |
byte |
getByte(int columnIndex) |
double |
getDouble(int columnIndex) |
float |
getFloat(int columnIndex) |
int |
getInt(int columnIndex) |
long |
getLong(int columnIndex) |
java.lang.Object |
getObject(int columnIndex) |
short |
getShort(int columnIndex) |
java.lang.String |
getString(int columnIndex) |
java.sql.SQLWarning |
getWarnings() |
boolean |
next() |
static SimpleJsonVTI |
readArray(org.json.simple.JSONArray array)
Create a SimpleJsonVTI from a JSONArray object.
|
boolean |
wasNull() |
absolute, afterLast, beforeFirst, cancelRowUpdates, deleteRow, findColumn, first, getArray, getArray, getAsciiStream, getAsciiStream, getBigDecimal, getBigDecimal, getBigDecimal, getBinaryStream, getBinaryStream, getBlob, getBlob, getBoolean, getByte, getBytes, getBytes, getCharacterStream, getCharacterStream, getClob, getClob, getConcurrency, getContext, getCursorName, getDate, getDate, getDate, getDate, getDouble, getFetchDirection, getFetchSize, getFloat, getHoldability, getInt, getLong, getMetaData, getNCharacterStream, getNCharacterStream, getNClob, getNClob, getNString, getNString, getObject, getObject, getObject, getObject, getObject, getRef, getRef, getReturnTableSignature, getRow, getRowId, getRowId, getShort, getSQLXML, getSQLXML, getStatement, getString, getTime, getTime, getTime, getTime, getTimestamp, getTimestamp, getTimestamp, getTimestamp, getType, getUnicodeStream, getUnicodeStream, getURL, getURL, insertRow, isAfterLast, isBeforeFirst, isClosed, isFirst, isLast, isWrapperFor, last, moveToCurrentRow, moveToInsertRow, previous, refreshRow, relative, rowDeleted, rowInserted, rowUpdated, setContext, setFetchDirection, setFetchSize, unwrap, updateArray, updateArray, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateBigDecimal, updateBigDecimal, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBoolean, updateBoolean, updateByte, updateByte, updateBytes, updateBytes, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateClob, updateClob, updateClob, updateClob, updateClob, updateClob, updateDate, updateDate, updateDouble, updateDouble, updateFloat, updateFloat, updateInt, updateInt, updateLong, updateLong, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNString, updateNString, updateNull, updateNull, updateObject, updateObject, updateObject, updateObject, updateRef, updateRef, updateRow, updateRowId, updateRowId, updateShort, updateShort, updateSQLXML, updateSQLXML, updateString, updateString, updateTime, updateTime, updateTimestamp, updateTimestamp
public static SimpleJsonVTI readArray(org.json.simple.JSONArray array) throws java.sql.SQLException
Create a SimpleJsonVTI from a JSONArray object.
java.sql.SQLException
public void close() throws java.sql.SQLException
java.sql.SQLException
public boolean next() throws java.sql.SQLException
java.sql.SQLException
public boolean wasNull()
wasNull
in interface java.sql.ResultSet
wasNull
in class VTITemplate
public java.sql.SQLWarning getWarnings() throws java.sql.SQLException
getWarnings
in interface java.sql.ResultSet
getWarnings
in class VTITemplate
java.sql.SQLException
public void clearWarnings() throws java.sql.SQLException
clearWarnings
in interface java.sql.ResultSet
clearWarnings
in class VTITemplate
java.sql.SQLException
public java.lang.String getString(int columnIndex) throws java.sql.SQLException
getString
in interface java.sql.ResultSet
getString
in class VTITemplate
java.sql.SQLException
public boolean getBoolean(int columnIndex) throws java.sql.SQLException
getBoolean
in interface java.sql.ResultSet
getBoolean
in class VTITemplate
java.sql.SQLException
public byte getByte(int columnIndex) throws java.sql.SQLException
getByte
in interface java.sql.ResultSet
getByte
in class VTITemplate
java.sql.SQLException
public short getShort(int columnIndex) throws java.sql.SQLException
getShort
in interface java.sql.ResultSet
getShort
in class VTITemplate
java.sql.SQLException
public int getInt(int columnIndex) throws java.sql.SQLException
getInt
in interface java.sql.ResultSet
getInt
in class VTITemplate
java.sql.SQLException
public long getLong(int columnIndex) throws java.sql.SQLException
getLong
in interface java.sql.ResultSet
getLong
in class VTITemplate
java.sql.SQLException
public float getFloat(int columnIndex) throws java.sql.SQLException
getFloat
in interface java.sql.ResultSet
getFloat
in class VTITemplate
java.sql.SQLException
public double getDouble(int columnIndex) throws java.sql.SQLException
getDouble
in interface java.sql.ResultSet
getDouble
in class VTITemplate
java.sql.SQLException
public java.lang.Object getObject(int columnIndex) throws java.sql.SQLException
getObject
in interface java.sql.ResultSet
getObject
in class VTITemplate
java.sql.SQLException
public java.math.BigDecimal getBigDecimal(int columnIndex) throws java.sql.SQLException
getBigDecimal
in interface java.sql.ResultSet
getBigDecimal
in class VTITemplate
java.sql.SQLException
Apache Derby 10.13 API Documentation - Copyright © 2004,2016 The Apache Software Foundation. All Rights Reserved.