git.8kb.co.uk Git - postgresql/jsonb_delete/blob - jsonb_delete.c

   1 /*
   2  * jsonb_delete.c
   3  *     Test jsonb delete operator functions for 9.4+
   4  *
   5  * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
   6  * Portions Copyright (c) 1994, Regents of the University of California
   7  * Author: Glyn Astill <glyn@8kb.co.uk>
   8  *
   9  */
  10
  11 #include "postgres.h"
  12 #include "fmgr.h"
  13 #include "utils/jsonb.h"
  14 #include "utils/builtins.h"
  15 #include "jsonb_delete.h"
  16
  17 #ifdef PG_MODULE_MAGIC
  18         PG_MODULE_MAGIC;
  19 #endif
  20
  21 Datum jsonb_delete_jsonb(PG_FUNCTION_ARGS);
  22
  23 PG_FUNCTION_INFO_V1(jsonb_delete_jsonb);
  24
  25 /*
  26  * Operator function to delete top level keys and values from left operand
  27  * where a match is found in the right operand.
  28  *
  29  * jsonb, jsonb -> jsonb
  30  *
  31  */
  32 Datum
  33 jsonb_delete_jsonb(PG_FUNCTION_ARGS)
  34 {
  35     Jsonb                  *jb1 = PG_GETARG_JSONB(0);
  36     Jsonb                  *jb2 = PG_GETARG_JSONB(1);
  37     JsonbValue             *res = NULL;
  38     JsonbParseState        *state = NULL;
  39     JsonbIterator          *it, *it2;
  40     JsonbValue              v, v2;
  41     JsonbValue              key;
  42     JsonbValue             *lookup = NULL;
  43     int32                   r, r2;
  44     bool                    push = true;
  45
  46     /* check if right jsonb is empty and return left if so */
  47     if (JB_ROOT_COUNT(jb2) == 0)
  48         PG_RETURN_JSONB(jb1);
  49
  50     it = JsonbIteratorInit(&jb1->root);
  51
  52     while ((r = JsonbIteratorNext(&it, &v, true)) != WJB_DONE)
  53     {
  54         push = true;
  55
  56         switch (r)
  57         {
  58             case WJB_BEGIN_ARRAY:
  59             case WJB_BEGIN_OBJECT:
  60             case WJB_END_ARRAY:
  61             case WJB_END_OBJECT:
  62                 res = pushJsonbValue(&state, r, NULL);
  63                 break;
  64             case WJB_ELEM:
  65                 if (v.type == jbvBinary)
  66                 {
  67                     it2 = JsonbIteratorInit(&jb2->root);
  68                     while ((r2 = JsonbIteratorNext(&it2, &v2, true)) != WJB_DONE)
  69                     {
  70                         if (v2.type == jbvBinary && v2.val.binary.len == v.val.binary.len &&
  71                             memcmp(v2.val.binary.data, v.val.binary.data, v2.val.binary.len) == 0)
  72                         {
  73                                 push = false;
  74                                 break;
  75                         }
  76                     }
  77                 }
  78                 else if (findJsonbValueFromContainer(&jb2->root, JB_FARRAY, &v) != NULL)
  79                     push = false;
  80
  81                 if (push)
  82                 {
  83                     if (v.type == jbvBinary)
  84                         res = pushJsonbBinary(&state, v.val.binary.data);
  85                     else
  86                         res = pushJsonbValue(&state, WJB_ELEM, &v);
  87                 }
  88                 break;
  89             case WJB_KEY:
  90                 lookup = findJsonbValueFromContainer(&jb2->root, JB_FOBJECT, &v);
  91
  92                 key = v;
  93                 r = JsonbIteratorNext(&it, &v, true);
  94
  95                 Assert(r == WJB_VALUE);
  96
  97                 if (lookup != NULL && lookup->type == v.type)
  98                 {
  99                     switch (lookup->type)
 100                     {
 101                         /* Nulls within json are equal, but should not be equal to SQL nulls */
 102                         case jbvNull:
 103                             push = false;
 104                             break;
 105                         case jbvNumeric:
 106                             if (DatumGetBool(DirectFunctionCall2(numeric_eq,
 107                                                                  PointerGetDatum(lookup->val.numeric),
 108                                                                  PointerGetDatum(v.val.numeric))))
 109                                 push = false;
 110                             break;
 111                         case jbvString:
 112                             if ((lookup->val.string.len == v.val.string.len) &&
 113                                 (memcmp(lookup->val.string.val,
 114                                         v.val.string.val,
 115                                         lookup->val.string.len) == 0))
 116                                 push = false;
 117                             break;
 118                         case jbvBinary:
 119                             if ((lookup->val.binary.len == v.val.binary.len) &&
 120                                 (memcmp(lookup->val.binary.data,
 121                                         v.val.binary.data,
 122                                         lookup->val.binary.len) == 0))
 123                                 push = false;
 124                                 break;
 125                         case jbvBool:
 126                             if (lookup->val.boolean == v.val.boolean)
 127                                 push = false;
 128                             break;
 129                         default:
 130                             ereport(ERROR, (errcode(ERRCODE_SUCCESSFUL_COMPLETION), errmsg("unrecognized lookup type: %d", (int) lookup->type)));
 131                         /* inner switch end */
 132                     }
 133                 }
 134
 135                 if (push)
 136                 {
 137                     res = pushJsonbValue(&state, WJB_KEY, &key);
 138
 139                     /* if our value is nested binary data, iterate separately pushing each val */
 140                     if (v.type == jbvBinary)
 141                         res = pushJsonbBinary(&state, v.val.binary.data);
 142                     else
 143                         res = pushJsonbValue(&state, r, &v);
 144                 }
 145                 break;
 146             case WJB_VALUE:
 147                 /* should not be possible */
 148             default:
 149                 elog(ERROR, "impossible state: %d", r);
 150             /* switch end */
 151         }
 152
 153     }
 154
 155     if (JB_ROOT_IS_SCALAR(jb1) && !res->val.array.rawScalar && res->val.array.nElems == 1)
 156         res->val.array.rawScalar = true;
 157
 158     PG_FREE_IF_COPY(jb1, 0);
 159     PG_FREE_IF_COPY(jb2, 1);
 160
 161     PG_RETURN_JSONB(JsonbValueToJsonb(res));
 162 }
 163