forked from apache/spark-website
-
Notifications
You must be signed in to change notification settings - Fork 0
/
error-message-guidelines.html
586 lines (521 loc) · 24.1 KB
/
error-message-guidelines.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>
Error message guidelines | Apache Spark
</title>
<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" rel="stylesheet"
integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link href="https://fonts.googleapis.com/css2?family=DM+Sans:ital,wght@0,400;0,500;0,700;1,400;1,500;1,700&Courier+Prime:wght@400;700&display=swap" rel="stylesheet">
<link href="/css/custom.css" rel="stylesheet">
<!-- Code highlighter CSS -->
<link href="/css/pygments-default.css" rel="stylesheet">
<link rel="icon" href="/favicon.ico" type="image/x-icon">
</head>
<body class="global">
<nav class="navbar navbar-expand-lg navbar-dark p-0 px-4" style="background: #1D6890;">
<a class="navbar-brand" href="/">
<img src="/images/spark-logo-rev.svg" alt="" width="141" height="72">
</a>
<button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarContent"
aria-controls="navbarContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse col-md-12 col-lg-auto pt-4" id="navbarContent">
<ul class="navbar-nav me-auto">
<li class="nav-item">
<a class="nav-link active" aria-current="page" href="/downloads.html">Download</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="libraries" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Libraries
</a>
<ul class="dropdown-menu" aria-labelledby="libraries">
<li><a class="dropdown-item" href="/sql/">SQL and DataFrames</a></li>
<li><a class="dropdown-item" href="/streaming/">Spark Streaming</a></li>
<li><a class="dropdown-item" href="/mllib/">MLlib (machine learning)</a></li>
<li><a class="dropdown-item" href="/graphx/">GraphX (graph)</a></li>
<li>
<hr class="dropdown-divider">
</li>
<li><a class="dropdown-item" href="/third-party-projects.html">Third-Party Projects</a></li>
</ul>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="documentation" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Documentation
</a>
<ul class="dropdown-menu" aria-labelledby="documentation">
<li><a class="dropdown-item" href="/docs/latest/">Latest Release</a></li>
<li><a class="dropdown-item" href="/documentation.html">Older Versions and Other Resources</a></li>
<li><a class="dropdown-item" href="/faq.html">Frequently Asked Questions</a></li>
</ul>
</li>
<li class="nav-item">
<a class="nav-link active" aria-current="page" href="/examples.html">Examples</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="community" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Community
</a>
<ul class="dropdown-menu" aria-labelledby="community">
<li><a class="dropdown-item" href="/community.html">Mailing Lists & Resources</a></li>
<li><a class="dropdown-item" href="/contributing.html">Contributing to Spark</a></li>
<li><a class="dropdown-item" href="/improvement-proposals.html">Improvement Proposals (SPIP)</a>
</li>
<li><a class="dropdown-item" href="https://issues.apache.org/jira/browse/SPARK">Issue Tracker</a>
</li>
<li><a class="dropdown-item" href="/powered-by.html">Powered By</a></li>
<li><a class="dropdown-item" href="/committers.html">Project Committers</a></li>
<li><a class="dropdown-item" href="/history.html">Project History</a></li>
</ul>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="developers" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Developers
</a>
<ul class="dropdown-menu" aria-labelledby="developers">
<li><a class="dropdown-item" href="/developer-tools.html">Useful Developer Tools</a></li>
<li><a class="dropdown-item" href="/versioning-policy.html">Versioning Policy</a></li>
<li><a class="dropdown-item" href="/release-process.html">Release Process</a></li>
<li><a class="dropdown-item" href="/security.html">Security</a></li>
</ul>
</li>
</ul>
<ul class="navbar-nav ml-auto">
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="apacheFoundation" role="button"
data-bs-toggle="dropdown" aria-expanded="false">
Apache Software Foundation
</a>
<ul class="dropdown-menu" aria-labelledby="apacheFoundation">
<li><a class="dropdown-item" href="https://www.apache.org/">Apache Homepage</a></li>
<li><a class="dropdown-item" href="https://www.apache.org/licenses/">License</a></li>
<li><a class="dropdown-item"
href="https://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li>
<li><a class="dropdown-item" href="https://www.apache.org/foundation/thanks.html">Thanks</a></li>
<li><a class="dropdown-item" href="https://www.apache.org/security/">Security</a></li>
<li><a class="dropdown-item" href="https://www.apache.org/events/current-event">Event</a></li>
</ul>
</li>
</ul>
</div>
</nav>
<div class="container">
<div class="row mt-4">
<div class="col-12 col-md-9">
<h2 id="error-message-guidelines">Error Message Guidelines</h2>
<p>This guide is a reference for composing standardized and actionable
error messages in Apache Spark.</p>
<h3 id="include-what-why-and-how">Include What, Why, and How</h3>
<p>Exceptions thrown from Spark should answer the Five W’s and How:</p>
<ul>
<li><strong>Who</strong> encountered the problem?</li>
<li><strong>What</strong> was the problem?</li>
<li><strong>When</strong> did the problem happen?</li>
<li><strong>Where</strong> did the problem happen?</li>
<li><strong>Why</strong> did the problem happen?</li>
<li><strong>How</strong> can the problem be solved?</li>
</ul>
<p>The context provided by exceptions can help answer <strong>who</strong> (usually the
user), <strong>when</strong> (usually included in the log via <code>log4j</code>), and <strong>where</strong>
(usually included in the stack trace). However, these answers alone are
often insufficient for the user to solve the problem. An error message
that answers the remaining questions
— <strong>what</strong>, <strong>why</strong>, and <strong>how</strong> — minimizes user frustration.</p>
<h4 id="explicitly-answer-what-why-and-how">Explicitly answer What, Why and How</h4>
<p>In many cases, the error message should explicitly answer <strong>what</strong>,
<strong>why</strong>, and <strong>how</strong>.</p>
<h5 id="example-1">Example 1</h5>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/569fb133d09e24e4ed56ed7efff641512d98b01b/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L160">
Unable to generate an encoder for inner class {} without access to the
scope that this class was defined in. Try moving this class out of its
parent class.
</a>
</code></p>
<ul>
<li><strong>What:</strong> Unable to generate encoder inner class.</li>
<li><strong>Why:</strong> Did not have access to the scope that the class was defined in.</li>
<li><strong>How:</strong> Try moving this class out of its parent class.</li>
</ul>
<h5 id="example-2">Example 2</h5>
<p>If the proposed fix (<strong>how</strong>) feels arbitrary, providing an explanation
for <strong>why</strong> the error occurred can reduce user frustration.</p>
<p><strong>Before</strong></p>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/03dd33cc982ebb3de4354274ac49da31521b8195/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L498">
<span style="background-color: #ffcccc">Unsupported</span> function name {}.
</a>
</code></p>
<ul>
<li><strong>What:</strong> Unsupported function name.</li>
<li><strong>Why:</strong> Unclear.</li>
<li><strong>How:</strong> Unclear.</li>
</ul>
<p><strong>After</strong></p>
<p><em>Function name {} <span style="background-color: #ccffcc">is invalid. Temporary functions cannot belong to a
catalog. Specify a function name with one or two parts.</span></em></p>
<ul>
<li><strong>What:</strong> Invalid function name.</li>
<li><strong>Why:</strong> Temporary functions cannot belong to a catalog.</li>
<li><strong>How:</strong> Specify a function name with one or two parts.</li>
</ul>
<h4 id="implicitly-answer-how">Implicitly answer How</h4>
<p>Not all error messages should be this verbose. Sometimes, explicitly
explaining <strong>how</strong> to resolve the problem would be redundant;
you may skip an explicit explanation in this case.</p>
<h5 id="example-1-1">Example 1</h5>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/e5d972e84e973d9a2e62312dc471df30c35269bc/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L63">
Invalid pivot column {}. Pivot columns must be comparable.
</a>
</code></p>
<ul>
<li><strong>What:</strong> Invalid pivot column.</li>
<li><strong>Why:</strong> Pivot columns must be comparable.</li>
<li><strong>How (</strong><strong><em>implied by Why</em></strong><strong>):</strong> Use comparable pivot columns.</li>
</ul>
<h5 id="example-2-1">Example 2</h5>
<p><strong>Before</strong></p>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/9809a2f1c5187205c81542dbdc84b71db535f6e1/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L325">
Cannot specify window frame for {} function
</a>
</code></p>
<ul>
<li><strong>What:</strong> Cannot specify window frame for the function.</li>
<li><strong>Why</strong>: Unclear.</li>
<li><strong>How:</strong> Unclear.</li>
</ul>
<p><strong>After</strong></p>
<p><code style="white-space:normal">
Cannot specify frame for window expression {}. <span style="background-color: #ccffcc">Window expression
contains mismatch between function frame {} and specification frame {}.</span>
</code></p>
<ul>
<li><strong>What:</strong> Cannot specify the frame for the window expression.</li>
<li><strong>Why:</strong> Window expression contains mismatch between function frame
and specification frame.</li>
<li><strong>How (</strong><strong><em>implied by Why</em></strong><strong>):</strong> Match the function frame and
specification frame.</li>
</ul>
<h5 id="example-3">Example 3</h5>
<p><strong>Before</strong></p>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/aff6c0febb40d9713895ba00d8c77ba00f04bd16/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryExecutionErrors.scala#L93">
Cannot parse any decimal.
</a>
</code></p>
<ul>
<li><strong>What:</strong> Cannot parse decimal.</li>
<li><strong>Why</strong>: Unclear.</li>
<li><strong>How:</strong> Unclear.</li>
</ul>
<p><strong>After</strong></p>
<p><code style="white-space:normal">
Invalid decimal {}; <span style="background-color: #ccffcc">encountered error while parsing at position {}.</span>
</code></p>
<ul>
<li><strong>What:</strong> Invalid decimal.</li>
<li><strong>Why</strong>: The decimal parser encountered an error at the specified position.</li>
<li><strong>How (</strong><strong><em>implied by Why</em></strong><strong>):</strong> Fix the error at the specified position.</li>
</ul>
<h4 id="implicitly-answer-why-and-how">Implicitly answer Why and How</h4>
<p>Sometimes, even explicitly explaining <strong>why</strong> the problem happened would
be redundant; you may skip an explicit explanation in this case.</p>
<p><code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/569fb133d09e24e4ed56ed7efff641512d98b01b/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L770">
Path does not exist: {}
</a>
</code></p>
<ul>
<li><strong>What:</strong> Path does not exist.</li>
<li><strong>Why (</strong><strong><em>implied by What</em></strong><strong>):</strong> User specified an invalid path.</li>
<li><strong>How (</strong><strong><em>implied by What</em></strong><strong>):</strong> Use a different path.</li>
</ul>
<h3 id="use-clear-language">Use clear language</h3>
<h4 id="diction-guide">Diction guide</h4>
<table class="table table-hover">
<thead>
<tr>
<th scope="col">Phrases</th>
<th scope="col">When to use</th>
<th scope="col">Example</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">Unsupported</th>
<td>
The user may reasonably assume that the operation is supported, but it is not. This error may go away in the future if developers add support for the operation.
</td>
<td>
<code style="white-space:normal">
Data type {} is <span style="background-color: #ccffff">unsupported</span>.
</code>
</td>
</tr>
<tr>
<th rowspan="3" scope="rowgroup">
Invalid / Not allowed / Unexpected
</th>
<td rowspan="3">
The user made a mistake when specifying an operation. The message should inform the user of how to resolve the error.
</td>
<td>
<code style="white-space:normal">
Array has size {}, index {} is <span style="background-color: #ccffff">invalid</span>.
</code>
</td>
</tr>
<tr>
<td>
<code style="white-space:normal">
Found {} generators for the clause {}. Only one generator is <span style="background-color: #ccffff">allowed</span>.
</code>
</td>
</tr>
<tr>
<td>
<code style="white-space:normal">
Found an <span style="background-color: #ccffff">unexpected</span> state format version {}. Expected versions 1 or 2.
</code>
</td>
</tr>
<tr>
<th scope="row">Failed to</th>
<td>
The system encountered an unexpected error that cannot be reasonably attributed to user error.
</td>
<td>
<code style="white-space:normal">
<span style="background-color: #ccffff">Failed to</span> compile {}.
</code>
</td>
</tr>
<tr>
<th scope="row">Cannot</th>
<td>
Any time, preferably only if one of the above alternatives does not apply.
</td>
<td>
<code style="white-space:normal">
<span style="background-color: #ccffff">Cannot</span> generate code for unsupported type {}.
</code>
</td>
</tr>
</tbody>
</table>
<h4 id="wording-guide">Wording guide</h4>
<table class="table table-hover">
<thead>
<tr>
<th scope="col">Best practice</th>
<th scope="col">Before</th>
<th scope="col">After</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">
Use active voice
</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/73857cdd87757d2888bd92f6b7c2fad709701484/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L704">
DataType {} is <span style="background-color: #ffcccc">not supported by</span> {}.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
{} <span style="background-color: #ccffcc">does not</span> support datatype {}.
</code>
</td>
</tr>
<tr>
<th rowspan="2" scope="rowgroup">
Avoid time-based statements, such as promises of future support
</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/27bec91bc971b393bd91f2ec8c6483b33f844f12/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L185">
Pandas UDF aggregate expressions are <span style="background-color: #ffcccc">currently</span> not supported in pivot.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
Pivot <span style="background-color: #ccffcc">does not</span> support Pandas UDF aggregate expressions.
</code>
</td>
</tr>
<tr>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/569fb133d09e24e4ed56ed7efff641512d98b01b/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L1076">
Parquet type not <span style="background-color: #ffcccc">yet</span> supported: {}.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
{} <span style="background-color: #ccffcc">does not</span> support Parquet type.
</code>
</td>
</tr>
<tr>
<th rowspan="2" scope="rowgroup">Use the present tense to describe the error and provide suggestions</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/9809a2f1c5187205c81542dbdc84b71db535f6e1/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L166">
<span style="background-color: #ffcccc">Couldn't</span> find the reference column for {} at {}.
</a>
</code>
</td>
<td>
<code style="white-space:normal"><span style="background-color: #ccffcc">Cannot</span> find the reference column for {} at {}.</code>
</td>
</tr>
<tr>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/9809a2f1c5187205c81542dbdc84b71db535f6e1/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L409">
Join strategy hint parameter <span style="background-color: #ffcccc">should be</span> an identifier or string but was {}.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
Cannot use join strategy hint parameter {}. <span style="background-color: #ccffcc">Use</span> a table name or identifier to specify the parameter.
</code>
</td>
</tr>
<tr>
<th scope="row">Provide concrete examples if the resolution is unclear</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/569fb133d09e24e4ed56ed7efff641512d98b01b/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L422">
{} Hint expects a partition number as a parameter.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
{} Hint expects a partition number as a parameter. <span style="background-color: #ccffcc">For example, specify 3 partitions with {}(3)</span>.
</code>
</td>
</tr>
<tr>
<th scope="row">Avoid sounding accusatory, judgmental, or insulting</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/569fb133d09e24e4ed56ed7efff641512d98b01b/core/src/main/scala/org/apache/spark/resource/ResourceUtils.scala#L143">
<span style="background-color: #ffcccc">You must</span> specify an amount for {}.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
{} cannot be empty. Specify an amount for {}.
</code>
</td>
</tr>
<tr>
<th scope="row">Be direct</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/4b5fc1da752ec008468ef80a5717c8beab468387/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L119">
LEGACY store assignment policy is disallowed in Spark data source V2. <span style="background-color: #ffcccc">Please</span> set the configuration spark.sql.storeAssignmentPolicy to <span style="background-color: #ffcccc">other values</span>.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
Spark data source V2 does not allow the LEGACY store assignment policy. Set the configuration spark.sql.storeAssignment to ANSI or STRICT.
</code>
</td>
</tr>
<tr>
<th scope="row">Do not use programming jargon in user-facing errors</th>
<td>
<code style="white-space:normal">
<a href="https://github.com/apache/spark/blob/4b5fc1da752ec008468ef80a5717c8beab468387/sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryCompilationErrors.scala#L583">
RENAME TABLE source and destination databases do not match: '{}' <span style="background-color: #ffcccc">!=</span> '{}'.
</a>
</code>
</td>
<td>
<code style="white-space:normal">
RENAME TABLE source and destination databases do not match. The source database is {}, but the destination database is {}.
</code>
</td>
</tr>
</tbody>
</table>
</div>
<div class="col-12 col-md-3">
<div class="news" style="margin-bottom: 20px;">
<h5>Latest News</h5>
<ul class="list-unstyled">
<li><a href="/news/spark-3-4-0-released.html">Spark 3.4.0 released</a>
<span class="small">(Apr 13, 2023)</span></li>
<li><a href="/news/spark-3-2-4-released.html">Spark 3.2.4 released</a>
<span class="small">(Apr 13, 2023)</span></li>
<li><a href="/news/spark-3-3-2-released.html">Spark 3.3.2 released</a>
<span class="small">(Feb 17, 2023)</span></li>
<li><a href="/news/spark-3-2-3-released.html">Spark 3.2.3 released</a>
<span class="small">(Nov 28, 2022)</span></li>
</ul>
<p class="small" style="text-align: right;"><a href="/news/index.html">Archive</a></p>
</div>
<div style="text-align:center; margin-bottom: 20px;">
<a href="https://www.apache.org/events/current-event.html">
<img src="https://www.apache.org/events/current-event-234x60.png" style="max-width: 100%;"/>
</a>
</div>
<div class="hidden-xs hidden-sm">
<a href="/downloads.html" class="btn btn-cta btn-lg d-grid" style="margin-bottom: 30px;">
Download Spark
</a>
<p style="font-size: 16px; font-weight: 500; color: #555;">
Built-in Libraries:
</p>
<ul class="list-none">
<li><a href="/sql/">SQL and DataFrames</a></li>
<li><a href="/streaming/">Spark Streaming</a></li>
<li><a href="/mllib/">MLlib (machine learning)</a></li>
<li><a href="/graphx/">GraphX (graph)</a></li>
</ul>
<a href="/third-party-projects.html">Third-Party Projects</a>
</div>
</div>
</div>
<footer class="small">
<hr>
Apache Spark, Spark, Apache, the Apache feather logo, and the Apache Spark project logo are either registered
trademarks or trademarks of The Apache Software Foundation in the United States and other countries.
See guidance on use of Apache Spark <a href="/trademarks.html">trademarks</a>.
All other marks mentioned may be trademarks or registered trademarks of their respective owners.
Copyright © 2018 The Apache Software Foundation, Licensed under the
<a href="https://www.apache.org/licenses/">Apache License, Version 2.0</a>.
</footer>
</div>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js"
integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM"
crossorigin="anonymous"></script>
<script src="https://code.jquery.com/jquery.js"></script>
<script src="/js/lang-tabs.js"></script>
<script src="/js/downloads.js"></script>
</body>
</html>