--- title: "in_search_path" slug: "dev-database-reference-sql-functions-utility-in-search-path" updated: 2026-10-30T18:18:46Z published: 2026-10-30T18:18:46Z canonical: "docs.vastdata.com/dev-database-reference-sql-functions-utility-in-search-path" --- > ## Documentation Index > Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt > Use this file to discover all available pages before exploring further. # in_search_path *Applies to VAST Cluster 5.5.* *[Functions](/develop/docs/dev-database-reference-sql-functions-index) › [Session and utility functions](/develop/docs/dev-database-reference-sql-functions-utility) › Session and diagnostics.* Returns `true` if the schema `schema_name` of the database `database_name` is in the Query Engine's search path, and `false` if it isn't. ## Syntax ``` in_search_path(database_name, schema_name) ``` | Argument | Type | Description | | --- | --- | --- | | `database_name` | `VARCHAR` | The database (catalog) name. | | `schema_name` | `VARCHAR` | The schema name. | **Returns:** `BOOLEAN`. ## Set up the examples The examples connect with the ADBC driver, as in [VAST Query Engine (ADBC)](/develop/docs/dev-database-integrations-adbc), and work in a schema called `docs_sql_fn_string_in_search_path`. Set `QE_ENDPOINT`, `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY` and `VASTDB_BUCKET` ([SQL reference](/develop/docs/dev-database-reference-sql-index#example-connect-and-use-a-transaction)), and run the blocks in order in one Python session. Below each block is the output you should see. This block connects, defines the `run()` and `plan()` helpers, and creates a table of database and schema names to test. The last row has no values: ``` import os import re import adbc_driver_manager import adbc_driver_manager.dbapi as dbapi import adbc_driver_vastdb BUCKET = os.environ["VASTDB_BUCKET"] SCHEMA = f'"{BUCKET}/docs_sql_fn_string_in_search_path"' conn = dbapi.connect( driver=adbc_driver_vastdb.get_driver_path(), db_kwargs={ "vast.db.endpoint": os.environ["QE_ENDPOINT"], "vast.db.access_key": os.environ["AWS_ACCESS_KEY_ID"], "vast.db.secret_key": os.environ["AWS_SECRET_ACCESS_KEY"], }, autocommit=True, ) def server_message(e): """The server's message in a driver error, without the request ID or the echoed statement.""" text = re.sub(r"\[req=0x[0-9a-f]+\]: ", "", str(e)) found = (re.search(r'message: "(.*?)", request_id', text, re.S) or re.search(r"description: (.*)\)", text, re.S)) message = found.group(1) if found else text.strip().splitlines()[-1] message = re.sub(r"^Plan query: '.*?' failed with: ", "", message, flags=re.S) message = re.split(r"\\n|\n", message)[0].replace('\\"', '"') return message.replace(BUCKET, "") def run(sql): """Run one statement. Print the rows it returns, or the error.""" try: with conn.cursor() as cur: cur.execute(sql) rows = cur.fetchall() if cur.description else [] except (adbc_driver_manager.Error, OSError) as e: print(f"{type(e).__name__}: {server_message(e)}") else: print(rows) def plan(sql): """Print the plan without its ~N Rows lines: the table's row count, which can still be 0 just after an insert.""" with conn.cursor() as cur: cur.execute("EXPLAIN " + sql) steps = cur.fetchall()[0][1] print("\n".join(line for line in steps.splitlines() if "Rows" not in line)) TABLE = f"{SCHEMA}.paths" run(f"CREATE SCHEMA IF NOT EXISTS {SCHEMA}") run(f"CREATE TABLE IF NOT EXISTS {TABLE} (id BIGINT, db VARCHAR, sch VARCHAR)") run(f"INSERT INTO {TABLE} VALUES " "(1, 'system', 'main'), " "(2, 'temp', 'main'), " "(3, 'memory', 'main'), " "(4, 'no_db', 'no_schema'), " "(5, NULL, 'main')") ``` ``` [] [] [(5,)] ``` ## What it does `in_search_path` checks one pair of names against the search path and returns a `BOOLEAN`. Names that don't exist aren't an error: they return `false`. Both arguments can be columns, so you can test many pairs in one query. The setting `search_path`, which [current_setting](/develop/docs/dev-database-reference-sql-functions-utility-current-setting) reads, is an empty string on a new connection, as the last example shows. The examples in these docs name tables in full, as `"bucket/schema".table`. ## NULLs and edge cases | Input | Result | | --- | --- | | Either name `NULL` | `NULL` | | `('system', 'main')`, `('temp', 'main')` | `true` | | `('memory', 'main')` | `false` | | A name that doesn't exist | `false` | | `('', '')` | `false` | | A number | Error: `No function matches the given name and argument types 'in_search_path(INTEGER_LITERAL, VARCHAR)'` | The same cases, as the cluster returns them. They use the table and helpers from [Set up the examples](/develop/docs/dev-database-reference-sql-functions-utility-in-search-path#set-up-the-examples): ``` run("SELECT in_search_path(NULL, 'main'), in_search_path('memory', NULL), in_search_path('system', 'main'), " "in_search_path('temp', 'main'), in_search_path('memory', 'main'), in_search_path('no_db', 'no_schema'), " "in_search_path('', '')") run("SELECT in_search_path(123, 'main')") ``` ``` [(None, None, True, True, False, False, False)] InternalError: Binder Error: No function matches the given name and argument types 'in_search_path(INTEGER_LITERAL, STRING_LITERAL)'. You might need to add explicit type casts. ``` ## Examples Test each pair in the table: ``` run(f"SELECT id, db, sch, in_search_path(db, sch) FROM {TABLE} ORDER BY id LIMIT 10") ``` ``` [(1, 'system', 'main', True), (2, 'temp', 'main', True), (3, 'memory', 'main', False), (4, 'no_db', 'no_schema', False), (5, None, 'main', None)] ``` Test your own bucket and the examples' schema: ``` run(f"SELECT in_search_path('{BUCKET}', 'docs_sql_fn_string_in_search_path'), current_setting('search_path')") ``` ``` [(False, '')] ``` Keep the pairs that are in the search path: ``` run(f"SELECT id, db, sch FROM {TABLE} WHERE in_search_path(db, sch) ORDER BY id LIMIT 10") ``` ``` [(1, 'system', 'main'), (2, 'temp', 'main')] ``` ## How it runs in VAST The Query Engine runs on the cluster's CNodes, and a query on a table starts with a scan in VAST DataBase (`VAST_SCAN`). `in_search_path()` is a function of columns, so it's computed by the Query Engine: - **In the `SELECT` list,** the scan reads the columns and the Query Engine computes the result for each row it returns. - **In `WHERE`,** the scan sends the columns for every row, and a `FILTER` step in the Query Engine keeps the rows that pass. The plan of the `WHERE` example shows the `FILTER` step above the scan: ``` plan(f"SELECT id FROM {TABLE} WHERE in_search_path(db, sch)") ``` ``` ┌───────────────────────────┐ │ PROJECTION │ │ ──────────────────── │ │ #2 │ │ │ └─────────────┬─────────────┘ ┌─────────────┴─────────────┐ │ FILTER │ │ ──────────────────── │ │ in_search_path(db, sch) │ │ │ └─────────────┬─────────────┘ ┌─────────────┴─────────────┐ │ VAST_SCAN │ │ ──────────────────── │ │ Function: VAST_SCAN │ │ │ │ Projections: │ │ db │ │ sch │ │ id │ │ │ └───────────────────────────┘ ``` ## Make it faster - **Combine it with a pushed-down condition.** In `id > 100 AND in_search_path(db, sch)`, `id > 100` can be evaluated in VAST DataBase, so the function runs only on the rows that pass it. See [pushdowns](/develop/docs/dev-database-reference-pushdowns). ## Limitations and errors - **Two `VARCHAR` arguments.** A number fails with `No function matches the given name and argument types`. - **Unknown names return `false`, not an error.** Check the spelling of a name before you rely on a `false`. ## Similar functions | Function | Returns | | --- | --- | | `in_search_path` | Whether a database and schema are in the search path | | [current_setting](/develop/docs/dev-database-reference-sql-functions-utility-current-setting) with `'search_path'` | The value of the `search_path` setting, as a `VARCHAR` | ``` run("SELECT in_search_path('system', 'main'), current_setting('search_path')") ``` ``` [(True, '')] ``` Clean up: ``` run(f"DROP TABLE IF EXISTS {TABLE}") run(f"DROP SCHEMA IF EXISTS {SCHEMA}") conn.close() ``` ``` [] [] ``` ## See also - [current_setting](/develop/docs/dev-database-reference-sql-functions-utility-current-setting): read a Query Engine setting. - [Where filters run](/develop/docs/dev-database-reference-sql-select#where-filters-run) and [pushdowns](/develop/docs/dev-database-reference-pushdowns). - [EXPLAIN](/develop/docs/dev-database-reference-sql-explain): how to read a plan.