jsonpath-and-jsonblisted

PostgreSQL's SQL/JSON support — jsonpath (SQL:2016 path language) + jsonb (binary-encoded JSON) + the SQL/JSON operators like `->`, `->>`, `@?`, `@@`, `jsonb_path_query`. Covers `src/backend/utils/adt/jsonb*.c` (jsonb storage + operators + GIN opclass + subscripting) and `jsonpath*.c` (path language parser + executor). Loads when the user asks about jsonpath semantics, path variables ($, @, current), lax vs strict mode, predicate expressions, `jsonb_path_query` / `jsonb_path_exists`, JSON_TABLE (SQL:2023 / PG 17+), jsonb_gin operator class, memory management in jsonpath_exec (Tom Lane's 5a2043bf713 rewrite), or "why is my JSON search slow" (usually GIN or path complexity). Skip when the ask is about the older `json` type (`json.c` is separate — text representation) or about JSON output formats (that's `format_type` territory).
matejformanek/postgres-claude · ★ 0 · AI & Automation · score 70

Install: claude install-skill matejformanek/postgres-claude

# jsonpath-and-jsonb — SQL/JSON path language and binary JSON PG has TWO JSON types: - **`json`** — text storage. Preserves formatting/whitespace/key-order. Slow to query (parsed every access). - **`jsonb`** — binary storage. Deduped/sorted keys, faster to query, indexable via GIN. Almost always what you want. Plus **`jsonpath`** — a query language type (SQL:2016). Compiled path expressions used by `jsonb_path_query`, `jsonb_path_exists`, `@@` operator, `JSON_TABLE`. ## The file map | File | KB | Role | |---|---:|---| | `utils/adt/jsonb.c` | 47 | Public `jsonb` operators + I/O — `jsonb_in`, `jsonb_out`, `jsonb_object`, `->`, `->>`, key existence `?`, containment `@>`. | | `utils/adt/jsonb_util.c` | 58 | Internal serialization + traversal. `JsonbIterator`, `findJsonbValueFromContainer`, packing helpers. Contains ordering/deduplication rules. | | `utils/adt/jsonb_gin.c` | 35 | GIN opclass for jsonb — extract-value / extract-query / consistent functions. Multiple index shapes: default, path_ops. | | `utils/adt/jsonb_op.c` | 7 | Small operator wrappers. | | `utils/adt/jsonbsubs.c` | 12 | Array/object subscripting — `jsonb['key']` (PG 14+). | | `utils/adt/jsonpath.c` | 38 | jsonpath type support — parser (via `jsonpath_scan.l` + `jsonpath_gram.y`), I/O, tree walks. | | `utils/adt/jsonpath_exec.c` | **127** | jsonpath EXECUTOR. `executeItem`, `executePredicate`, `executeBinaryArithmExpr` — traverses the jsonpath tree against a jsonb value. **This is where the leak fix landed**