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1# OH_Predicates
2
3## Overview
4
5Defines a **predicates** object.
6
7**Since**: 10
8
9**Related module**: [RDB](capi-rdb.md)
10
11**Header file**: [oh_predicates.h](capi-oh-predicates-h.md)
12
13### Member Variables
14
15| Name      | Description                            |
16| ---------- | -------------------------------- |
17| int64_t id | Unique identifier of the **H_Predicates** struct.|
18
19### Member Functions
20
21| Name                                                        | Description                                                        |
22| ------------------------------------------------------------ | ------------------------------------------------------------ |
23| [OH_Predicates *(*equalTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#equalto) | Pointer to the function used to create a predicates object to search for the field values that are equal to the specified value.          |
24| [OH_Predicates *(*notEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#notequalto) | Pointer to the function used to create a predicates object to search for the field values that are not equal to the specified value.<br>This method is equivalent to "!=" in SQL statements.|
25| [OH_Predicates *(*beginWrap)(OH_Predicates *predicates)](#beginwrap) | Pointer to the function used to add a left parenthesis to the predicates.<br>This method is equivalent to "(" in SQL statements.|
26| [OH_Predicates *(*endWrap)(OH_Predicates *predicates)](#endwrap) | Pointer to the function used to add a right parenthesis to the predicates.<br>This method is equivalent to ")" in SQL statements.|
27| [OH_Predicates *(*orOperate)(OH_Predicates *predicates)](#oroperate) | Pointer to the function used to add the OR operator to the predicates.<br>This method is equivalent to **OR** in SQL statements.|
28| [OH_Predicates *(*andOperate)(OH_Predicates *predicates)](#andoperate) | Pointer to the function used to add the AND operator to the predicates.<br>This method is equivalent to **AND** in SQL statements.|
29| [OH_Predicates *(*isNull)(OH_Predicates *predicates, const char *field)](#isnull) | Pointer to the function used to create a predicates object to search for the field values that are null.<br>This method is equivalent to **IS NULL** in SQL statements.|
30| [OH_Predicates *(*isNotNull)(OH_Predicates *predicates, const char *field)](#isnotnull) | Pointer to the function used to create a predicates object to search for the field values that are not null.<br>This method is equivalent to **IS NOT NULL** in SQL statements.|
31| [OH_Predicates *(*like)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#like) | Pointer to the function used to create a predicates object to search for the field values that are similar to the specified string.<br>This method is equivalent to **LIKE** in SQL statements.|
32| [OH_Predicates *(*between)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#between) | Pointer to the function used to create a predicates object to search for the field values that are within the specified range.<br>This method is equivalent to **BETWEEN** in SQL statements.|
33| [OH_Predicates *(*notBetween)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#notbetween) | Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.<br>This method is equivalent to **NOT BETWEEN** in SQL statements.|
34| [OH_Predicates *(*greaterThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#greaterthan) | Pointer to the function used to create a predicates object to search for the field values that are greater than the specified value.<br>This method is equivalent to ">" in SQL statements.|
35| [OH_Predicates *(*lessThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#lessthan) | Pointer to the function used to create a predicates object to search for the records that are less than the given value in the specified field.<br>This method is equivalent to "<" in SQL statements.|
36| [OH_Predicates *(*greaterThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#greaterthanorequalto) | Pointer to the function used to create a predicates object to search for the field values that are greater than or equal to the specified value.<br>This method is equivalent to ">=" in SQL statements.|
37| [OH_Predicates *(*lessThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#lessthanorequalto) | Pointer to the function used to create a predicates object to search for the records that are less than or equal to the specified **valueObject** in the specified field.<br>This method is equivalent to "<=" in SQL statements.|
38| [OH_Predicates *(*orderBy)(OH_Predicates *predicates, const char *field, OH_OrderType type)](#orderby) | Pointer to the function used to create a predicates object to sort the values in the specified column in ascending or descending order.<br>This method is equivalent to **ORDER BY** in SQL statements.|
39| [OH_Predicates *(*distinct)(OH_Predicates *predicates)](#distinct) | Pointer to the function used to create a predicates object to filter out duplicate records.<br>This method is equivalent to **DISTINCT** in SQL statements.|
40| [OH_Predicates *(*limit)(OH_Predicates *predicates, unsigned int value)](#limit) | Pointer to the function used to create a predicates object to specify the maximum number of records.<br>This method is equivalent to **LIMIT** in SQL statements.|
41| [OH_Predicates *(*offset)(OH_Predicates *predicates, unsigned int rowOffset)](#offset) | Pointer to the function used to create a predicates object to specify the start position of the query result.<br>This method is equivalent to **OFFSET** in SQL statements.|
42| [OH_Predicates *(*groupBy)(OH_Predicates *predicates, char const *const *fields, int length)](#groupby) | Pointer to the function used to create a predicates object to group the results by the specified columns.<br>This method is equivalent to **GROUP BY** in SQL statements.|
43| [OH_Predicates *(*in)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#in) | Pointer to the function used to create a predicates object to search for the field values that are within the specified range.<br>This method is equivalent to **IN** in SQL statements.|
44| [OH_Predicates *(*notIn)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)](#notin) | Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.<br>This method is equivalent to **NOT IN** in SQL statements.|
45| [OH_Predicates *(*clear)(OH_Predicates *predicates)](#clear) | Pointer to the function used to clear a predicates instance.                                        |
46| [int (*destroy)(OH_Predicates *predicates)](#destroy)        | Destroys an **OH_Predicates** object and reclaims the memory occupied.             |
47
48
49## Member Function Description
50
51### equalTo()
52
53```
54OH_Predicates *(*equalTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
55```
56
57**Description**
58
59Pointer to the function used to create a predicates object to search for the field values that are equal to the specified value.
60
61**Since**: 10
62
63**Parameters**
64
65| Name                   | Description                                                        |
66| ------------------------- | ------------------------------------------------------------ |
67| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.                           |
68| const char *field         | Pointer to the column name in the database table.                                            |
69| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject   | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
70
71**Returns**
72
73| Type           | Description                      |
74| --------------- | -------------------------- |
75| OH_Predicates * | Predicates that match the specified field.|
76
77### notEqualTo()
78
79```
80OH_Predicates *(*notEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
81```
82
83**Description**
84
85Pointer to the function used to create a predicates object to search for the field values that are not equal to the specified value.<br>This method is equivalent to "!=" in SQL statements.
86
87**Since**: 10
88
89**Parameters**
90
91| Name                                       | Description                                                        |
92| --------------------------------------------- | ------------------------------------------------------------ |
93| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
94| const char *field                             | Column name in the database table.                                          |
95| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
96
97**Returns**
98
99| Type           | Description                      |
100| --------------- | -------------------------- |
101| OH_Predicates * | Predicates that match the specified field.|
102
103### beginWrap()
104
105```
106OH_Predicates *(*beginWrap)(OH_Predicates *predicates)
107```
108
109**Description**
110
111Pointer to the function used to add a left parenthesis to the predicates.<br>This method is equivalent to "(" in SQL statements.
112
113**Since**: 10
114
115**Parameters**
116
117| Name                  | Description                             |
118| ------------------------ | --------------------------------- |
119| H_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
120
121**Returns**
122
123| Type           | Description                  |
124| --------------- | ---------------------- |
125| OH_Predicates * | Predicates with a left parenthesis.|
126
127### endWrap()
128
129```
130OH_Predicates *(*endWrap)(OH_Predicates *predicates)
131```
132
133**Description**
134
135Pointer to the function used to add a right parenthesis to the predicates.<br>This method is equivalent to ")" in SQL statements.
136
137**Since**: 10
138
139**Parameters**
140
141| Name                   | Description                             |
142| ------------------------- | --------------------------------- |
143| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
144
145**Returns**
146
147| Type           | Description                  |
148| --------------- | ---------------------- |
149| OH_Predicates * | Predicates with a right parenthesis.|
150
151### orOperate()
152
153```
154OH_Predicates *(*orOperate)(OH_Predicates *predicates)
155```
156
157**Description**
158
159Pointer to the function used to add the OR operator to the predicates.<br>This method is equivalent to **OR** in SQL statements.
160
161**Since**: 10
162
163**Parameters**
164
165| Name                   | Description                             |
166| ------------------------- | --------------------------------- |
167| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
168
169**Returns**
170
171| Type           | Description                  |
172| --------------- | ---------------------- |
173| OH_Predicates * | Predicates with the OR condition.|
174
175### andOperate()
176
177```
178OH_Predicates *(*andOperate)(OH_Predicates *predicates)
179```
180
181**Description**
182
183Pointer to the function used to add the AND operator to the predicates.<br>This method is equivalent to **AND** in SQL statements.
184
185**Since**: 10
186
187**Parameters**
188
189| Name                   | Description                             |
190| ------------------------- | --------------------------------- |
191| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
192
193**Returns**
194
195| Type           | Description                  |
196| --------------- | ---------------------- |
197| OH_Predicates * | Predicates with the AND condition.|
198
199### isNull()
200
201```
202OH_Predicates *(*isNull)(OH_Predicates *predicates, const char *field)
203```
204
205**Description**
206
207Pointer to the function used to create a predicates object to search for the field values that are null.<br>This method is equivalent to **IS NULL** in SQL statements.
208
209**Since**: 10
210
211**Parameters**
212
213| Name                   | Description                             |
214| ------------------------- | --------------------------------- |
215| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
216| const char *field         | Column name in the database table.               |
217
218**Returns**
219
220| Type           | Description                      |
221| --------------- | -------------------------- |
222| OH_Predicates * | Predicates that match the specified field.|
223
224### isNotNull()
225
226```
227OH_Predicates *(*isNotNull)(OH_Predicates *predicates, const char *field)
228```
229
230**Description**
231
232Pointer to the function used to create a predicates object to search for the field values that are not null.<br>This method is equivalent to **IS NOT NULL** in SQL statements.
233
234**Since**: 10
235
236**Parameters**
237
238| Name                   | Description                             |
239| ------------------------- | --------------------------------- |
240| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
241| const char *field         | Column name in the database table.               |
242
243**Returns**
244
245| Type           | Description                      |
246| --------------- | -------------------------- |
247| OH_Predicates * | Predicates that match the specified field.|
248
249### like()
250
251```
252OH_Predicates *(*like)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
253```
254
255**Description**
256
257Pointer to the function used to create a predicates object to search for the field values that are similar to the specified string.<br>This method is equivalent to **LIKE** in SQL statements.
258
259**Since**: 10
260
261**Parameters**
262
263| Name                                       | Description                                                        |
264| --------------------------------------------- | ------------------------------------------------------------ |
265| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
266| const char *field                             | Column name in the database table.                                          |
267| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
268
269**Returns**
270
271| Type           | Description                      |
272| --------------- | -------------------------- |
273| OH_Predicates * | Predicates that match the specified field.|
274
275
276### between()
277
278```
279OH_Predicates *(*between)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
280```
281
282**Description**
283
284Pointer to the function used to create a predicates object to search for the field values that are within the specified range.<br>This method is equivalent to **BETWEEN** in SQL statements.
285
286**Since**: 10
287
288**Parameters**
289
290| Name                                       | Description                                                        |
291| --------------------------------------------- | ------------------------------------------------------------ |
292| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
293| const char *field                             | Column name in the database table.                                          |
294| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
295
296**Returns**
297
298| Type           | Description                      |
299| --------------- | -------------------------- |
300| OH_Predicates * | Predicates that match the specified field.|
301
302### notBetween()
303
304```
305OH_Predicates *(*notBetween)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
306```
307
308**Description**
309
310Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.<br>This method is equivalent to **NOT BETWEEN** in SQL statements.
311
312**Since**: 10
313
314**Parameters**
315
316| Name                                       | Description                                                        |
317| --------------------------------------------- | ------------------------------------------------------------ |
318| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
319| const char *field                             | Column name in the database table.                                          |
320| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
321
322**Returns**
323
324| Type           | Description                      |
325| --------------- | -------------------------- |
326| OH_Predicates * | Predicates that match the specified field.|
327
328### greaterThan()
329
330```
331OH_Predicates *(*greaterThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
332```
333
334**Description**
335
336Pointer to the function used to create a predicates object to search for the field values that are greater than the specified value.<br>This method is equivalent to ">" in SQL statements.
337
338**Since**: 10
339
340**Parameters**
341
342| Name                                       | Description                                                        |
343| --------------------------------------------- | ------------------------------------------------------------ |
344| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
345| const char *field                             | Column name in the database table.                                          |
346| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
347
348**Returns**
349
350| Type           | Description                      |
351| --------------- | -------------------------- |
352| OH_Predicates * | Predicates that match the specified field.|
353
354### lessThan()
355
356```
357OH_Predicates *(*lessThan)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
358```
359
360**Description**
361
362Pointer to the function used to create a predicates object to search for the records that are less than the given value in the specified field.<br>This method is equivalent to "<" in SQL statements.
363
364**Since**: 10
365
366**Parameters**
367
368| Name                                       | Description                                                        |
369| --------------------------------------------- | ------------------------------------------------------------ |
370| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
371| const char *field                             | Column name in the database table.                                          |
372| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
373
374**Returns**
375
376| Type           | Description                      |
377| --------------- | -------------------------- |
378| OH_Predicates * | Predicates that match the specified field.|
379
380### greaterThanOrEqualTo()
381
382```
383OH_Predicates *(*greaterThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
384```
385
386**Description**
387
388Pointer to the function used to create a predicates object to search for the field values that are greater than or equal to the specified value.<br>This method is equivalent to ">=" in SQL statements.
389
390**Since**: 10
391
392**Parameters**
393
394| Name                                       | Description                                                        |
395| --------------------------------------------- | ------------------------------------------------------------ |
396| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
397| const char *field                             | Column name in the database table.                                          |
398| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
399
400**Returns**
401
402| Type           | Description                      |
403| --------------- | -------------------------- |
404| OH_Predicates * | Predicates that match the specified field.|
405
406### lessThanOrEqualTo()
407
408```
409OH_Predicates *(*lessThanOrEqualTo)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
410```
411
412**Description**
413
414Pointer to the function used to create a predicates object to search for the records that are less than or equal to the specified **valueObject** in the specified field.<br>This method is equivalent to "<=" in SQL statements.
415
416**Since**: 10
417
418**Parameters**
419
420| Name                   | Description                                                        |
421| ------------------------- | ------------------------------------------------------------ |
422| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.                           |
423| const char *field         | Column name in the database table.                                          |
424| OH_VObject *valueObject   | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
425
426**Returns**
427
428| Type           | Description                      |
429| --------------- | -------------------------- |
430| OH_Predicates * | Predicates that match the specified field.|
431
432### orderBy()
433
434```
435OH_Predicates *(*orderBy)(OH_Predicates *predicates, const char *field, OH_OrderType type)
436```
437
438**Description**
439
440Pointer to the function used to create a predicates object to sort the values in the specified column in ascending or descending order.<br>This method is equivalent to **ORDER BY** in SQL statements.
441
442**Since**: 10
443
444**Parameters**
445
446| Name                               | Description                                          |
447| ------------------------------------- | ---------------------------------------------- |
448| OH_Predicates *predicates             | Pointer to the **OH_Predicates** instance.             |
449| const char *field                     | Column name in the database table.                            |
450| [OH_VObject](capi-rdb-oh-vobject.md) type | Sorting type, which is an [OH_VObject](capi-rdb-oh-vobject.md).|
451
452**Returns**
453
454| Type           | Description                      |
455| --------------- | -------------------------- |
456| OH_Predicates * | Predicates that match the specified field.|
457
458### distinct()
459
460```
461OH_Predicates *(*distinct)(OH_Predicates *predicates)
462```
463
464**Description**
465
466Pointer to the function used to create a predicates object to filter out duplicate records.<br>This method is equivalent to **DISTINCT** in SQL statements.
467
468**Since**: 10
469
470**Parameters**
471
472| Name                   | Description                             |
473| ------------------------- | --------------------------------- |
474| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
475
476**Returns**
477
478| Type           | Description                          |
479| --------------- | ------------------------------ |
480| OH_Predicates * | Predicates that can filter out duplicate records.|
481
482### limit()
483
484```
485OH_Predicates *(*limit)(OH_Predicates *predicates, unsigned int value)
486```
487
488**Description**
489
490Pointer to the function used to create a predicates object to specify the maximum number of records.<br>This method is equivalent to **LIMIT** in SQL statements.
491
492**Since**: 10
493
494**Parameters**
495
496| Name                   | Description                             |
497| ------------------------- | --------------------------------- |
498| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
499| unsigned int value        | Maximum number of data records.             |
500
501**Returns**
502
503| Type           | Description                                |
504| --------------- | ------------------------------------ |
505| OH_Predicates * | Predicates that specify the maximum number of records.|
506
507### offset()
508
509```
510OH_Predicates *(*offset)(OH_Predicates *predicates, unsigned int rowOffset)
511```
512
513**Description**
514
515Pointer to the function used to create a predicates object to specify the start position of the query result.<br>This method is equivalent to **OFFSET** in SQL statements.
516
517**Since**: 10
518
519**Parameters**
520
521| Name                   | Description                              |
522| ------------------------- | ---------------------------------- |
523| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance. |
524| unsigned int rowOffset    | Start position, which is a positive integer.|
525
526**Returns**
527
528| Type           | Description                                |
529| --------------- | ------------------------------------ |
530| OH_Predicates * | Predicates that specify the start position of the returned result.|
531
532### groupBy()
533
534```
535OH_Predicates *(*groupBy)(OH_Predicates *predicates, char const *const *fields, int length)
536```
537
538**Description**
539
540Pointer to the function used to create a predicates object to group the results by the specified columns.<br>This method is equivalent to **GROUP BY** in SQL statements.
541
542**Since**: 10
543
544**Parameters**
545
546| Name                   | Description                                                |
547| ------------------------- | ---------------------------------------------------- |
548| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.                   |
549| char const *const *fields | Names of columns to group.                                |
550| int length                | Length of **fields**.|
551
552**Returns**
553
554| Type           | Description                  |
555| --------------- | ---------------------- |
556| OH_Predicates * | Predicates that group rows with the same value.|
557
558### in()
559
560```
561OH_Predicates *(*in)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
562```
563
564**Description**
565
566Pointer to the function used to create a predicates object to search for the field values that are within the specified range.<br>This method is equivalent to **IN** in SQL statements.
567
568**Since**: 10
569
570**Parameters**
571
572| Name                                       | Description                                                        |
573| --------------------------------------------- | ------------------------------------------------------------ |
574| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
575| const char *field                             | Pointer to the column name in the database table.                                      |
576| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
577
578**Returns**
579
580| Type           | Description                      |
581| --------------- | -------------------------- |
582| OH_Predicates * | Predicates that match the specified field.|
583
584### notIn()
585
586```
587OH_Predicates *(*notIn)(OH_Predicates *predicates, const char *field, OH_VObject *valueObject)
588```
589
590**Description**
591
592Pointer to the function used to create a predicates object to search for the field values that are out of the specified range.<br>This method is equivalent to **NOT IN** in SQL statements.
593
594**Since**: 10
595
596**Parameters**
597
598| Name                                       | Description                                                        |
599| --------------------------------------------- | ------------------------------------------------------------ |
600| OH_Predicates *predicates                     | Pointer to the **OH_Predicates** instance.                           |
601| const char *field                             | Pointer to the column name in the database table.                                      |
602| [OH_VObject](capi-rdb-oh-vobject.md) *valueObject | Pointer to an [OH_VObject](capi-rdb-oh-vobject.md) instance, indicating the value to be matched with the predicate.|
603
604**Returns**
605
606| Type           | Description                      |
607| --------------- | -------------------------- |
608| OH_Predicates * | Predicates that match the specified field.|
609
610### clear()
611
612```
613OH_Predicates *(*clear)(OH_Predicates *predicates)
614```
615
616**Description**
617
618Clears a predicates instance.
619
620**Since**: 10
621
622**Parameters**
623
624| Name                   | Description                             |
625| ------------------------- | --------------------------------- |
626| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
627
628**Returns**
629
630| Type           | Description              |
631| --------------- | ------------------ |
632| OH_Predicates * | Cleared predicates.|
633
634### destroy()
635
636```
637int (*destroy)(OH_Predicates *predicates)
638```
639
640**Description**
641
642Destroys an **OH_Predicates** object and reclaims the memory occupied.
643
644**Since**: 10
645
646**Parameters**
647
648| Name                   | Description                             |
649| ------------------------- | --------------------------------- |
650| OH_Predicates *predicates | Pointer to the **OH_Predicates** instance.|
651
652**Returns**
653
654| Type| Description                                      |
655| ---- | ------------------------------------------ |
656| int  | Returns **RDB_OK** if the operation is successful; returns an error code otherwise.|
657