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| sql_queries:canned-queries-named-parameters | sql_queries | canned-queries-named-parameters | Canned query parameters | Canned queries support named parameters, so if you include those in the SQL you will then be able to enter them using the form fields on the canned query page or by adding them to the URL. This means canned queries can be used to create custom JSON APIs based on a carefully designed SQL statement. Here's an example of a canned query with a named parameter: select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood; In the canned query metadata (here Using YAML for metadata as metadata.yaml ) it looks like this: databases: fixtures: queries: neighborhood_search: sql: |- select neighborhood, facet_cities.name, state from facetable join facet_cities on facetable.city_id = facet_cities.id where neighborhood like '%' || :text || '%' order by neighborhood title: Search neighborhoods Here's the equivalent using JSON (as metadata.json ): { "databases": { "fixtures": { "queries": { "neighborhood_search": { "sql": "select neighborhood, facet_cities.name, state\nfrom facetable\n join facet_cities on facetable.city_id = facet_cities.id\nwhere neighborhood like '%' || :text || '%'\norder by neighborhood", "title": "Search neighborhoods" } } } } } Note that we are using SQLite string concatenation here - the || operator - to add wildcard % characters to the string provided by the user. You can try this canned query out here: https://latest.datasette.io/fixtures/neighborhood_search?text=town In this example the :text named parameter is automatically extracted from the query using a regular expression. … | ["Running SQL queries", "Canned queries"] | [{"href": "https://latest.datasette.io/fixtures/neighborhood_search?text=town", "label": "https://latest.datasette.io/fixtures/neighborhood_search?text=town"}] |
| sql_queries:canned-queries-options | sql_queries | canned-queries-options | Additional canned query options | Additional options can be specified for canned queries in the YAML or JSON configuration. | ["Running SQL queries", "Canned queries"] | [] |
| sql_queries:canned-queries-writable | sql_queries | canned-queries-writable | Writable canned queries | Canned queries by default are read-only. You can use the "write": true key to indicate that a canned query can write to the database. See Controlling access to specific canned queries for details on how to add permission checks to canned queries, using the "allow" key. { "databases": { "mydatabase": { "queries": { "add_name": { "sql": "INSERT INTO names (name) VALUES (:name)", "write": true } } } } } This configuration will create a page at /mydatabase/add_name displaying a form with a name field. Submitting that form will execute the configured INSERT query. You can customize how Datasette represents success and errors using the following optional properties: on_success_message - the message shown when a query is successful on_success_redirect - the path or URL the user is redirected to on success on_error_message - the message shown when a query throws an error on_error_redirect - the path or URL the user is redirected to on error For example: { "databases": { "mydatabase": { "queries": { "add_name": { "sql": "INSERT INTO names (name) VALUES (:name)", "write": true, "on_success_message": "Name inserted", "on_success_redirect": "/mydatabase/names", "on_error_message": "Name insert failed", "on_error_redirect": "/mydatabase" } } } } } You can use "p… | ["Running SQL queries", "Canned queries"] | [] |
| sql_queries:canned-queries-magic-parameters | sql_queries | canned-queries-magic-parameters | Magic parameters | Named parameters that start with an underscore are special: they can be used to automatically add values created by Datasette that are not contained in the incoming form fields or query string. These magic parameters are only supported for canned queries: to avoid security issues (such as queries that extract the user's private cookies) they are not available to SQL that is executed by the user as a custom SQL query. Available magic parameters are: _actor_* - e.g. _actor_id , _actor_name Fields from the currently authenticated Actors . _header_* - e.g. _header_user_agent Header from the incoming HTTP request. The key should be in lower case and with hyphens converted to underscores e.g. _header_user_agent or _header_accept_language . _cookie_* - e.g. _cookie_lang The value of the incoming cookie of that name. _now_epoch The number of seconds since the Unix epoch. _now_date_utc The date in UTC, e.g. 2020-06-01 _now_datetime_utc The ISO 8601 datetime in UTC, e.g. 2020-06-24T18:01:07Z _random_chars_* - e.g. … | ["Running SQL queries", "Canned queries"] | [] |
| sql_queries:canned-queries-json-api | sql_queries | canned-queries-json-api | JSON API for writable canned queries | Writable canned queries can also be accessed using a JSON API. You can POST data to them using JSON, and you can request that their response is returned to you as JSON. To submit JSON to a writable canned query, encode key/value parameters as a JSON document: POST /mydatabase/add_message {"message": "Message goes here"} You can also continue to submit data using regular form encoding, like so: POST /mydatabase/add_message message=Message+goes+here There are three options for specifying that you would like the response to your request to return JSON data, as opposed to an HTTP redirect to another page. Set an Accept: application/json header on your request Include ?_json=1 in the URL that you POST to Include "_json": 1 in your JSON body, or &_json=1 in your form encoded body The JSON response will look like this: { "ok": true, "message": "Query executed, 1 row affected", "redirect": "/data/add_name" } The "message" and "redirect" values here will take into account on_success_message , on_success_redirect , on_error_message and on_error_redirect , if they have been set. | ["Running SQL queries", "Canned queries"] | [] |
| sql_queries:hide-sql | sql_queries | hide-sql | hide_sql | Canned queries default to displaying their SQL query at the top of the page. If the query is extremely long you may want to hide it by default, with a "show" link that can be used to make it visible. Add the "hide_sql": true option to hide the SQL query by default. | ["Running SQL queries", "Canned queries", "Additional canned query options"] | [] |
| sql_queries:fragment | sql_queries | fragment | fragment | Some plugins, such as datasette-vega , can be configured by including additional data in the fragment hash of the URL - the bit that comes after a # symbol. You can set a default fragment hash that will be included in the link to the canned query from the database index page using the "fragment" key. This example demonstrates both fragment and hide_sql : { "databases": { "fixtures": { "queries": { "neighborhood_search": { "sql": "select neighborhood, facet_cities.name, state\nfrom facetable join facet_cities on facetable.city_id = facet_cities.id\nwhere neighborhood like '%' || :text || '%' order by neighborhood;", "fragment": "fragment-goes-here", "hide_sql": true } } } } } See here for a demo of this in action. | ["Running SQL queries", "Canned queries", "Additional canned query options"] | [{"href": "https://github.com/simonw/datasette-vega", "label": "datasette-vega"}, {"href": "https://latest.datasette.io/fixtures#queries", "label": "See here"}] |