Re: Patch: Add tsmatch JSONPath operator for granular Full Text Search - Mailing list pgsql-hackers

> On Feb 27, 2026, at 13:59, Florents Tselai <florents.tselai@gmail.com> wrote:
>
>
>
> On Thu, Feb 26, 2026 at 8:48 AM Chao Li <li.evan.chao@gmail.com> wrote:
>
>
> > On Feb 1, 2026, at 19:02, Florents Tselai <florents.tselai@gmail.com> wrote:
> >
> >
> >
> >
> > On Mon, Jan 26, 2026 at 7:22 PM Florents Tselai <florents.tselai@gmail.com> wrote:
> > Hi,
> >
> > in real-life I work a lot with json & fts search, here's a feature I've always wished I had,
> > but never tackle it. Until yesterday that is.
> >
> > SELECT jsonb_path_query(doc, '$.comments[*] ? (@.user == "Alice" && @.body tsmatch "performance")');
> >
> > This patch introduces a tsmatch boolean operator to the JSONPath engine.
> > By integrating FTS natively into path expressions,
> > this operator allows for high-precision filtering of nested JSONB structures—
> > solving issues with structural ambiguity and query complexity.
> >
> > Currently, users must choose between two suboptimal paths for FTS-ing nested JSON:
> > - Imprecise Global Indexing
> > jsonb_to_tsvector aggregates text into a flat vector.
> > This ignores JSON boundaries, leading to false positives when the same key (e.g., "body")
> > appears in different contexts (e.g., a "Product Description" vs. a "Customer Review").
> >
> > - Complex SQL Workarounds
> > Achieving 100% precision requires unnesting the document via jsonb_array_elements and LATERAL joins.
> > This leads to verbose SQL and high memory overhead from generating intermediate heap tuples.
> >
> > One of the most significant advantages of tsmatch is its ability to participate in multi-condition predicates
> > within the same JSON object - something jsonb_to_tsvector cannot do.
> >
> > SELECT jsonb_path_query(doc, '$.comments[*] ? (@.user == "Alice" && @.body tsmatch "performance")');
> >
> > In a flat vector, the association between "Alice" and "performance" is lost.
> > tsmatch preserves this link by evaluating the FTS predicate in-place during path traversal.
> >
> > While the SQL/JSON standard (ISO/IEC 9075-2) does not explicitly define an FTS operator,
> > tsmatch is architecturally modeled after the standard-defined like_regex.
> >
> > The implementation follows the like_regex precedent:
> > it is a non-indexable predicate that relies on GIN path-matching for pruning and heap re-checks for precision.
> > Caching is scoped to the JsonPathExecContext,
> > ensuring 'compile-once' efficiency per execution without violating the stability requirements of prepared
statements.
> >
> > This initial implementation uses plainto_tsquery.
> > However, the grammar is designed to support a "mode" flag (similar to like_regex flags)
> > in future iterations to toggle between to_tsquery, websearch_to_tsquery, and phraseto_tsquery.
> >
> > Here's a v2, that implements the tsqparser clause
> >
> > So this should now work too
> >
> > select jsonb_path_query_array('["fast car", "slow car", "fast and furious"]', '$[*] ? (@ tsmatch "fast car"
tsqparser"w") <v2-0001-Add-tsmatch-JSONPath-operator-for-granular-Full-T.patch> 
>
> Hi Florents,
>
> Grant pinged me about this. I can review it in coming days. Can you please rebase it? I failed to apply to current
master.Also, the CF reported a failure test case, please take a look. 
>
>  Hi Evan,
> thanks for having a look. The conflict was due to the intro of pg_fallthrough. Not related to this patch .
>
> I noticed the failure too, but I'm having a hard time reproducing it tbh.
> This fails for Debian Trixie with Meson. The same with Autoconf passes...
>
> https://github.com/Florents-Tselai/postgres/runs/65098077968
>
>
>
>
> <v3-0001-Add-tsmatch-JSONPath-operator-for-granular-Full-T.patch>

I have reviewed v3 and traced a few test cases. Here comes my review comments:

1
```
+        <replaceable>string</replaceable> <literal>tsmatch</literal> <replaceable>string</replaceable>
+        <optional> <literal>tsconfig</literal> <replaceable>string</replaceable> </optional>
+        <optional> <literal>tsqparser</literal> <replaceable>string</replaceable> </optional>
```

For all “replaceable”, instead of “string”, would it be better to use something more descriptive? For example:
```
<replaceable>json_string</replaceable> <literal>tsmatch</literal> <replaceable>query</replaceable>
<optional> <literal>tsconfig</literal> <replaceable>config_name</replaceable> </optional>
<optional> <literal>tsqparser</literal> <replaceable>parser_mode</replaceable> </optional>
```

2 - jsonpath_gram.y
```
+static bool makeItemTsMatch(JsonPathParseItem *doc,
+                              JsonPathString *tsquery,
+                              JsonPathString *tsconfig,
+                              JsonPathString *tsquery_parser,
+                              JsonPathParseItem ** result,
+                              struct Node *escontext);
```

Format Nit: Looking at the existing code, the J in the second and following lines, should be placed in the same column
asthe J in the first line. 

3 - jsonpath_gram.y
```
+    | expr TSMATCH_P STRING_P
+    {
+        JsonPathParseItem *jppitem;
+        /* Pass NULL for tsconfig (3rd) and NULL for tsquery_parser (4th) */
+        if (! makeItemTsMatch($1, &$3, NULL, NULL, &jppitem, escontext))
+           YYABORT;
+        $$ = jppitem;
+    }
+    | expr TSMATCH_P STRING_P TSCONFIG_P STRING_P
+    {
+        JsonPathParseItem *jppitem;
+        /* Pass NULL for tsquery_parser (4th) */
+        if (! makeItemTsMatch($1, &$3, &$5, NULL, &jppitem, escontext))
+           YYABORT;
+        $$ = jppitem;
+    }
+    | expr TSMATCH_P STRING_P TSQUERYPARSER_P STRING_P
+    {
+        JsonPathParseItem *jppitem;
+        /* Pass NULL for tsconfig (3rd) */
+        if (! makeItemTsMatch($1, &$3, NULL, &$5, &jppitem, escontext))
+           YYABORT;
+        $$ = jppitem;
+    }
+    | expr TSMATCH_P STRING_P TSCONFIG_P STRING_P TSQUERYPARSER_P STRING_P
+    {
+        JsonPathParseItem *jppitem;
+        if (! makeItemTsMatch($1, &$3, &$5, &$7, &jppitem, escontext))
+           YYABORT;
+        $$ = jppitem;
+    }
```

Feels a little redundant, repeatedly calls makeItemTsMatch. See the attached diff for a simplification. But my version
isa bit longer in terms of number of lines. So, up to you. 

4 - jsonpath_gram.y
```
+static bool
+makeItemTsMatch(JsonPathParseItem *doc,
+             JsonPathString *tsquery,
+             JsonPathString *tsconfig,
+             JsonPathString *tsquery_parser,
+             JsonPathParseItem **result,
+             struct Node *escontext)
```

makeItemTsMatch doesn’t need to return a bool. Actually, now it never returns false, instead, it just ereport(ERROR).

5 - jsonpath.h
```
+        struct
+        {
+            int32        doc;
+            char       *tsquery;
+            uint32        tsquerylen;
+            int32        tsconfig;
+            char       *tsqparser;
+            uint32        tsqparser_len;
+        }            tsmatch;

+        struct
+        {
+            JsonPathParseItem *doc;
+            char       *tsquery;
+            uint32        tsquerylen;
+            JsonPathParseItem *tsconfig;
+            char       *tsqparser;
+            uint32        tsqparser_len;
+        }            tsmatch;
     }            value;
```

tsquerylen doesn’t have _ before len, and tsqparser_len, would it be better to make naming conventions consistent in
thesame structure? 

6 - jsonpath_exec.c
```
#include "tsearch/ts_utils.h"
#include "tsearch/ts_cache.h"
#include "utils/regproc.h"
#include "catalog/namespace.h"

static JsonPathBool
executeTsMatch(JsonPathItem *jsp, JsonbValue *str, JsonbValue *rarg,
void *param)
```

Why don’t put these includes to the header section together with other includes?

7 - jsonpath_exec.c
```
+            else
+            {
+                /*
+                 * Fallback or Error for unknown flags (should be caught by
+                 * parser)
+                 */
+                ereport(ERROR,
+                        (errcode(ERRCODE_SYNTAX_ERROR),
+                         errmsg("unrecognized tsqparser flag")));
+            }
```

This “else” should never be entered as the same check has been done by makeItemTsMatch. So, maybe just use an Assert
here,or pg_unreachable(). 

8 -  jsonpath_exec.c
```
+    /* Setup Context (Run ONLY once per predicate) */
+    if (!cxt->initialized)
```

While tracing this SQL:
```
evantest=# SELECT '{"tags": ["running", "jogging"]}'::jsonb
evantest-#   @@ '$.tags[*] ? (@ tsmatch "run" tsconfig "english")';
 ?column?
----------

(1 row)
```

I noticed that, when process “jogging”, cxt->initialized is still false, meaning that, the cxt is not reused across
arrayitems. Given the same tsconfig should apply to all array items, I think cxt should be reused. 

9 -  jsonpath_exec.c
```
+        /* Select Parser and Compile Query */
+        parser_mode = jsp->content.tsmatch.tsqparser;
+        parser_len = jsp->content.tsmatch.tsqparser_len;
+
+        if (parser_len > 0)
+        {
+            /* Dispatch based on flag */
+            if (pg_strncasecmp(parser_mode, "pl", parser_len) == 0)
```

Nit: parser_mode is only used inside if (parser_len > 0), it can be defined inside the “if”.

10 - jsonpath_gram.y
```
+             ereport(ERROR,
+                     (errcode(ERRCODE_SYNTAX_ERROR),
+                      errmsg("invalid tsquery_parser value: \"%s\"", tsquery_parser->val),
+                      errhint("Valid values are \"pl\", \"ph\", and \"w\".")));
```

When tested a case with an invalid parser, I got:
```
evantest=# SELECT '{"tags": ["running", "jogging"]}'::jsonb
                                        @? '$.tags[*] ? (@ tsmatch "run" tsconfig "english" tsqparser "pss")'; 
ERROR:  invalid tsquery_parser value: "pss@"
LINE 2:   @? '$.tags[*] ? (@ tsmatch "run" tsconfig "english" tsqpar...
             ^
HINT:  Valid values are "pl", "ph", and "w".
```

You can see the it shows a bad looking invalid value. I think that’s because tsquery_parser->val is not NULL
terminated.I fixed this problem with: 
```
errmsg("invalid tsquery_parser value: \"%.*s\"", (int) tsquery_parser->len, tsquery_parser->val),
```

This change is also included in the attached diff file.

11 - jsonpath.c
```
+            if (printBracketes)
+                appendStringInfoChar(buf, ')');
+            break;
+
             if (printBracketes)
                 appendStringInfoChar(buf, ')');
```

Duplicate code. Looks like a copy-pasto.

12 - jsonpath.c
```
+                /* Write the Main Query String */
+                appendBinaryStringInfo(buf,
+                                       &item->value.tsmatch.tsquerylen,
+                                       sizeof(item->value.tsmatch.tsquerylen));
+                appendBinaryStringInfo(buf,
+                                       item->value.tsmatch.tsquery,
+                                       item->value.tsmatch.tsquerylen);
+                appendStringInfoChar(buf, '\0');
```

I don’t think we need to manually append ‘\0’ after appendBinaryStringInfo. Looking at the header comment of
appendBinaryStringInfo,it says that a trailing null will be added. 
```
/*
* appendBinaryStringInfo
*
* Append arbitrary binary data to a StringInfo, allocating more space
* if necessary. Ensures that a trailing null byte is present.
*/
void
appendBinaryStringInfo(StringInfo str, const void *data, int datalen)
```

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/