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4
您好，我是 Netezza 的新手，我被要求开发自定义 Java 函数并交付 API。
我的问题是我是否可以根据给定的要求提供解决方案。这是要求。
我有一个表，我们将其命名为 Table1。我必须按行读取表并计算不同的值，当我的值有意义时，我必须将其插入到不同的表中。
只是我需要读取多行，计算多个值，当数据有意义时我可以输出它。
所以我的问题是，是否可以在 Netezza 自定义 Java UDTF 函数中读取多行并输出很少的行？
最佳答案
是的，可以读取n行并输出
没有人帮助我，所以我继续构建了该功能，并且运行良好。
三年后，我被要求分享解决方案。我现在不记得要求了，我也离开公司很久了。所以我粘贴了我编写的600行代码，当时我很天真，可能有更好的方法来做到这一点。如果你能理解它，你就会很幸运。
import java.sql.Timestamp;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import org.netezza.ae.Nzae;
import org.netezza.ae.NzaeApi;
import org.netezza.ae.NzaeApiGenerator;
import org.netezza.ae.NzaeDataTypes;
import org.netezza.ae.NzaeException;
import org.netezza.ae.NzaeMetadata;
import org.netezza.ae.NzaeRecord;
import org.netezza.ae.NzaeUtil;
public class viewResolver {
private static final Executor exec = Executors.newCachedThreadPool();
public static final void main(String[] args) {
try {
mainImpl(args);
} catch (Throwable t) {
System.err.println(t.toString());
NzaeUtil.logException(t, "main");
}
}
public static final void mainImpl(String[] args) {
NzaeApiGenerator helper = new NzaeApiGenerator();
while (true) {
final NzaeApi api = helper.getApi(NzaeApi.FUNCTION);
if (api.apiType == NzaeApi.FUNCTION) {
if (!helper.isRemote()) {
run(api.aeFunction);
break;
} else {
Runnable task = new Runnable() {
public void run() {
try {
viewResolver.run(api.aeFunction);
} finally {
api.aeFunction.close();
}
}
};
exec.execute(task);
}
}
}
helper.close();
}
public static int run(Nzae ae) {
try {
int ret = runReal(ae);
ae.done();
return ret;
} catch (NzaeException ex) {
ex.printStackTrace();
ae.userError(ex.getMessage());
ae.done();
throw ex;
} catch (Throwable ex) {
ex.printStackTrace();
ae.userError(ex.toString());
ae.done();
throw new NzaeException(ex.toString());
}
}
static String acc_id = null;
static String rec_id = null;
static String tuner = null;
static String channel = null;
static String show_name = null;
static String tmsId = null;
static String viewing_type = null;
static String event_type = null;
static String channelFamily = null;
static String ruid = null;
static int suid = 0;
static double timeStarted = 0;
static double timeEnded = 0;
static Timestamp datecreated = null;
static double content_start = 0;
static double content_end = 0;
static String prev_acc_id = null;
static String prev_rec_id = null;
static String prev_tuner = null;
static String prev_channel = null;
static String prev_show_name = null;
static String prev_tmsId = null;
static String prev_viewing_type = null;
static String prev_event_type = null;
static String prev_channelFamily = null;
static String prev_ruid = null;
static int prev_suid = 0;
static double prev_timeStarted = 0;
static double prev_timeEnded = 0;
static Timestamp prev_datecreated = null;
static double prev_content_start = 0;
static double prev_content_end = 0;
public static int runReal(Nzae ae) {
double dvr_time_watched = 0;
double vod_time_watched = 0;
double manual_ffx = 0;
double manual_ffr = 0;
boolean end = false;
double tune_duration = 0;
boolean live_DVR_Flag = false;
final NzaeMetadata meta = ae.getMetadata();
NzaeRecord input = null;
boolean firstRecord = true;
validateInput(meta);
while (!end) {
NzaeRecord output = ae.createOutputRecord();
if (true) {
input = ae.next();
if (input == null) {// checks if no more records
end = true;
// returns the final view
if (prev_timeEnded - prev_timeStarted != 0) {// if final view is tune
tune_duration = prev_timeEnded - prev_timeStarted;
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel, prev_show_name,
prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily, prev_ruid,
prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated, 0, 0, tune_duration,
manual_ffx, manual_ffr);
ae.outputResult(output);
}
if (vod_time_watched != 0 || dvr_time_watched != 0 || manual_ffr != 0 || manual_ffx != 0) {
if (!prev_event_type.equalsIgnoreCase("DVR_EOE") && dvr_time_watched != 0) {// if DVR
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, dvr_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
} else if (!prev_event_type.equalsIgnoreCase("DVR_EOE") && vod_time_watched != 0) {// if VOD
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, vod_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
}
}
continue;
} else {// set variables
if (input.getField(0) != null)
acc_id = input.getField(0).toString();
else
acc_id = null;
if (input.getField(1) != null)
rec_id = input.getField(1).toString();
else
rec_id = null;
if (input.getField(2) != null)
tuner = input.getField(2).toString();
else
tuner = null;
if (input.getField(3) != null)
channel = input.getField(3).toString();
else
channel = null;
if (input.getField(4) != null)
show_name = input.getField(4).toString();
else
show_name = null;
if (input.getField(5) != null)
tmsId = input.getField(5).toString();
else
tmsId = null;
if (input.getField(6) != null)
viewing_type = input.getField(6).toString();
else
viewing_type = null;
if (input.getField(7) != null)
event_type = input.getField(7).toString();
else
event_type = null;
if (input.getField(8) != null)
channelFamily = input.getField(8).toString();
else
channelFamily = null;
if (input.getField(9) != null)
ruid = input.getField(9).toString();
else
ruid = null;
if (input.getField(10) != null)
suid = input.getFieldAsNumber(10).intValue();
else
suid = 0;
if (input.getField(11) != null)
timeStarted = input.getFieldAsNumber(11).doubleValue();
else
timeStarted = 0;
if (input.getField(12) != null)
timeEnded = input.getFieldAsNumber(12).doubleValue();
else
timeEnded = 0;
if (input.getField(13) != null)
datecreated = input.getFieldAsTimestamp(13);
else
datecreated = null;
if (input.getField(14) != null)
content_start = input.getFieldAsNumber(14).doubleValue();
else
content_start = 0;
if (input.getField(15) != null)
content_end = input.getFieldAsNumber(15).doubleValue();
else
content_end = 0;
}
}
if (firstRecord) {
prev_acc_id = acc_id;
prev_rec_id = rec_id;
prev_tuner = tuner;
prev_channel = channel;
prev_show_name = show_name;
prev_tmsId = tmsId;
prev_viewing_type = viewing_type;
prev_event_type = event_type;
prev_channelFamily = channelFamily;
prev_ruid = ruid;
prev_suid = suid;
prev_timeStarted = timeStarted;
prev_timeEnded = timeEnded;
prev_datecreated = datecreated;
prev_content_start = content_start;
prev_content_end = content_end;
firstRecord = false;
}
// ********* if acc id or rec id changes
if (prev_acc_id != null && prev_rec_id != null && prev_acc_id != null && prev_rec_id != null) {
if (!prev_acc_id.equalsIgnoreCase(acc_id) || !prev_rec_id.equalsIgnoreCase(rec_id)) {
if (prev_timeEnded - prev_timeStarted != 0) {// if tune
tune_duration = prev_timeEnded - prev_timeStarted;
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel, prev_show_name,
prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily, prev_ruid,
prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated, 0, 0, tune_duration,
manual_ffx, manual_ffr);
ae.outputResult(output);
prev_timeEnded = prev_timeStarted = 0;
setPreviousValues();
tune_duration = 0;
manual_ffr = 0;
manual_ffx = 0;
}
if (dvr_time_watched != 0 || manual_ffr != 0 || manual_ffx != 0) {
if (!prev_event_type.equalsIgnoreCase("DVR_EOE")) {// if DVR
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, dvr_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
}
dvr_time_watched = 0;
manual_ffr = 0;
manual_ffx = 0;
setPreviousValues();
live_DVR_Flag = false;
}
if (vod_time_watched != 0 || manual_ffr != 0 || manual_ffx != 0) {
if (!prev_event_type.equalsIgnoreCase("DVR_EOE")) {// if VOD
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, vod_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
}
vod_time_watched = 0;
manual_ffr = 0;
manual_ffx = 0;
setPreviousValues();
live_DVR_Flag = false;
}
}
}
// ******** special case tune to DVR
if (viewing_type != null && prev_viewing_type != null)
if ((live_DVR_Flag || prev_viewing_type.equalsIgnoreCase("Tune"))
&& viewing_type.equalsIgnoreCase("DvrEvent")) {
if (tmsId != null)
if (!prev_tmsId.equalsIgnoreCase(tmsId)) {
if (live_DVR_Flag) {
// should change the event name to "Live DVR"
if (!prev_event_type.equalsIgnoreCase("DVR_EOE")) {
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, "LiveDVR", prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, dvr_time_watched, manual_ffx,
manual_ffr);
ae.outputResult(output);
}
dvr_time_watched = 0;
manual_ffr = 0;
manual_ffx = 0;
setPreviousValues();
live_DVR_Flag = false;
}
}
if (tmsId != null)
if (prev_tmsId.equalsIgnoreCase(tmsId))
if (event_type != null && content_start != 0 && content_end != 0) {
live_DVR_Flag = true;
// ******* total play time
if (event_type.equalsIgnoreCase("DVR_PLAY") || event_type.equalsIgnoreCase("DVR_PAUSE")) {
dvr_time_watched += (content_end - content_start);
}
// ********* total ffx time
if (event_type.contains("FWD_START") && !event_type.contains("SKIP")) {
manual_ffx += (content_end - content_start);
}
// ********** total ffr time
if (event_type.contains("FWD_END") && !event_type.contains("SKIP")) {
manual_ffr += (content_end - content_start);
}
}
}
// ******** special case DVR to tune
if (viewing_type != null && prev_viewing_type != null)
if ((live_DVR_Flag || prev_viewing_type.equalsIgnoreCase("DvrEvent"))
&& viewing_type.equalsIgnoreCase("Tune")) {
if (tmsId != null)
if (!prev_tmsId.equalsIgnoreCase(tmsId)) {
if (live_DVR_Flag) {
tune_duration = prev_timeEnded - prev_timeStarted;
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, "LiveDVR", prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated, 0, 0,
tune_duration, manual_ffx, manual_ffr);
ae.outputResult(output);
prev_timeEnded = prev_timeStarted = 0;
setPreviousValues();
tune_duration = 0;
manual_ffr = 0;
manual_ffx = 0;
live_DVR_Flag = false;
}
}
if (tmsId != null)
if (prev_tmsId.equalsIgnoreCase(tmsId))
if (timeEnded != 0)
prev_timeEnded = timeEnded;
}
// ***** For Tune events
if (prev_viewing_type.equalsIgnoreCase("Tune")) {
if (tmsId != null)
if (!prev_tmsId.equalsIgnoreCase(tmsId)) {
if (prev_timeEnded != 0) {
tune_duration = prev_timeEnded - prev_timeStarted;
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated, 0, 0,
tune_duration, manual_ffx, manual_ffr);
ae.outputResult(output);
prev_timeEnded = prev_timeStarted = 0;
setPreviousValues();
tune_duration = 0;
manual_ffr = 0;
manual_ffx = 0;
}
}
if (timeEnded != 0)
prev_timeEnded = timeEnded;
}
// ************ for DVR events
else if (prev_viewing_type.contains("DvrEvent")) {
if (tmsId != null)
if (!prev_tmsId.equalsIgnoreCase(tmsId)) {
if (!prev_event_type.equalsIgnoreCase("DVR_EOE")) {
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, dvr_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
}
dvr_time_watched = 0;
manual_ffr = 0;
manual_ffx = 0;
setPreviousValues();
}
if (event_type != null && content_start != 0 && content_end != 0) {
// ******* total play time
if (event_type.equalsIgnoreCase("DVR_PLAY") || event_type.equalsIgnoreCase("DVR_PAUSE")) {
dvr_time_watched += (content_end - content_start);
// play_end = row.getCONTENT_END_EPOCH();
}
// ********* total ffx time
if (event_type.contains("FWD_START") && !event_type.contains("SKIP")) {
manual_ffx += (content_end - content_start);
}
// ********** total ffr time
if (event_type.contains("FWD_END") && !event_type.contains("SKIP")) {
manual_ffr += (content_end - content_start);
}
}
}
// ************ for Vod events
else if (prev_viewing_type.equalsIgnoreCase("VODEvent")) {
if (ruid != null)
if (!prev_ruid.equalsIgnoreCase(ruid)) {
if (!prev_event_type.equalsIgnoreCase("DVR_EOE")) {
output = setOutput(output, prev_acc_id, prev_rec_id, prev_tuner, prev_channel,
prev_show_name, prev_tmsId, prev_viewing_type, prev_event_type, prev_channelFamily,
prev_ruid, prev_suid, prev_timeStarted, prev_timeEnded, prev_datecreated,
prev_content_start, prev_content_end, vod_time_watched, manual_ffx, manual_ffr);
ae.outputResult(output);
}
vod_time_watched = 0;
manual_ffr = 0;
manual_ffx = 0;
setPreviousValues();
}
if (event_type != null && content_start != 0 && content_end != 0) {
// ******* total play time
if (event_type.equalsIgnoreCase("DVR_PLAY") || event_type.equalsIgnoreCase("DVR_PAUSE")) {
vod_time_watched += (content_end - content_start);
// play_end = row.getCONTENT_END_EPOCH();
}
// ********* total ffx time
if (event_type.contains("FWD_START") && !event_type.contains("SKIP")) {
manual_ffx += (content_end - content_start);
}
// ********** total ffr time
if (event_type.contains("FWD_END") && !event_type.contains("SKIP")) {
manual_ffr += (content_end - content_start);
}
}
}
}
return 0;
}
/**
*
*/
private static void setPreviousValues() {
prev_acc_id = acc_id;
prev_rec_id = rec_id;
prev_tuner = tuner;
prev_channel = channel;
prev_show_name = show_name;
prev_tmsId = tmsId;
prev_viewing_type = viewing_type;
prev_event_type = event_type;
prev_channelFamily = channelFamily;
prev_ruid = ruid;
prev_suid = suid;
prev_timeStarted = timeStarted;
prev_timeEnded = timeEnded;
prev_datecreated = datecreated;
prev_content_start = content_start;
prev_content_end = content_end;
}
/**
* @param output
* @param accId
* @param recId
* @param string
* @param channel
* @param showName
* @param tmsId
* @param eventName
* @param eventType
* @param channelFamily
* @param ruid
* @param suid
* @param timeStarted
* @param timeEnded
* @param fieldAsTimestamp2
* @param contentStart
* @param contentEnd
* @param duration
* @param manualFfx
* @param manualFfr
*/
private static NzaeRecord setOutput(NzaeRecord output, String accId, String recId, String string, String channel,
String showName, String tmsId, String eventName, String eventType, String channelFamily, String ruid,
int suid, double timeStarted, double timeEnded, Timestamp fieldAsTimestamp2, double contentStart,
double contentEnd, double duration, double manualFfx, double manualFfr) {
output.setField(0, accId);
output.setField(1, recId);
output.setField(2, string);
output.setField(3, channel);
output.setField(4, showName);
output.setField(5, tmsId);
output.setField(6, eventName);
output.setField(7, eventType);
output.setField(8, channelFamily);
output.setField(9, ruid);
output.setField(10, suid == 0 ? null : suid);
output.setField(11, timeStarted == 0 ? null : timeStarted);
output.setField(12, timeEnded == 0 ? null : timeEnded);
output.setField(13, fieldAsTimestamp2);
output.setField(14, contentStart == 0 ? null : contentStart);
output.setField(15, contentEnd == 0 ? null : contentEnd);
output.setField(16, duration);
output.setField(17, manualFfx);
output.setField(18, manualFfr);
return output;
}
/**
* @param meta
*/
private static void validateInput(NzaeMetadata meta) {
if (meta.getOutputColumnCount() != 19) {
throw new NzaeException("expecting 19 output columns ");
}
if (meta.getInputColumnCount() != 16) {
throw new NzaeException("expecting 16 input columns");
}
if (meta.getInputNzType(0) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(0) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("first input column (Account id hashed) expected to be a string type");
}
if (meta.getInputNzType(1) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(1) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("second input column (Receiver id hashed) expected to be a string type");
}
if (meta.getInputNzType(2) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(2) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("third input column (Tuner) expected to be a string type");
}
if (meta.getInputNzType(3) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(3) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("fourth input column (Channel) expected to be a string type");
}
if (meta.getInputNzType(4) != NzaeDataTypes.NZUDSUDX_NATIONAL_FIXED
&& meta.getInputNzType(4) != NzaeDataTypes.NZUDSUDX_NATIONAL_VARIABLE) {
throw new NzaeException("fifth input column (Show name) expected to be a string type");
}
if (meta.getInputNzType(5) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(5) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("sixth input column (TMS_ID) expected to be a string type");
}
if (meta.getInputNzType(6) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(6) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("seventh input column (Event Name) expected to be a string type");
}
if (meta.getInputNzType(7) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(7) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("eighth input column (Event type) expected to be a string type");
}
if (meta.getInputNzType(8) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(8) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("nineth input column (CHANNEL_FAMILY) expected to be a string type");
}
if (meta.getInputNzType(9) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(9) != NzaeDataTypes.NZUDSUDX_VARIABLE) {
throw new NzaeException("thenth input column (RUID) expected to be a string type");
}
if (meta.getInputNzType(10) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(10) != NzaeDataTypes.NZUDSUDX_INT32) {
throw new NzaeException("eleventh input column (SUID) expected to be a integer type");
}
if (meta.getInputNzType(11) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(11) != NzaeDataTypes.NZUDSUDX_INT64) {
throw new NzaeException("twelfth input column (Start Epoch) expected to be a Big Integer type");
}
if (meta.getInputNzType(12) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(12) != NzaeDataTypes.NZUDSUDX_INT64) {
throw new NzaeException("thirteenth input column (End Epoch) expected to be a Big Integer type");
}
if (meta.getInputNzType(13) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(13) != NzaeDataTypes.NZUDSUDX_TIMESTAMP) {
throw new NzaeException("fourteenth input column (Date created) expected to be a timestamp type");
}
if (meta.getInputNzType(14) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(14) != NzaeDataTypes.NZUDSUDX_INT64) {
throw new NzaeException("fifteenth input column (Content start date) expected to be a Big Integer type");
}
if (meta.getInputNzType(15) != NzaeDataTypes.NZUDSUDX_FIXED
&& meta.getInputNzType(15) != NzaeDataTypes.NZUDSUDX_INT64) {
throw new NzaeException("sixteenth input column (Content end date) expected to be a big Integer type");
}
}
}
关于java - Netezza Java UDTF 自定义函数，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15707799/
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