pub fn json_insert_1<J: JsonOrNullableJsonOrJsonbOrNullableJsonb + MaybeNullableValue<Json> + SingleValue, V1: NotBlob, json, path_1, value_1>(
json: json,
path_1: path_1,
value_1: value_1,
) -> json_insert_1<J, V1, json, path_1, value_1>__sqlite-shared only.Expand description
The json_insert(X,P,V,...) SQL function takes a single JSON value as its first argument
followed by zero or more pairs of path and value arguments. It returns a copy of the X
argument with the values V inserted at the paths P, but only where nothing already exists at
§Variadic functions
This function is variadic in SQL, so there’s a family of functions on a diesel side:
json_insert_0, json_insert_1, … json_insert_n
Here, the postfix number indicates repetitions of variadic arguments. To use this function, the appropriate version with the correct argument count must be selected.
§Controlling the generation of variadic function variants
By default, only variants with 0, 1, and 2 repetitions of variadic
arguments are generated. To generate more variants, set the
DIESEL_VARIADIC_FUNCTION_ARGS environment variable to the desired
number of variants.
For a greater convenience this environment variable can also be set
in a .cargo/config.toml file as described in the
cargo documentation.
the path. Paths that already select an element of X are left unchanged.
The path/value pairs are applied sequentially from left to right.
A path that ends in [#] appends the value to an existing array.
If the json_insert(X) function is called with no path/value pairs, then it returns the
input X reformatted, with excess whitespace removed.
The json_insert() function throws an error if any of the path arguments is not a
well-formed path.
This function requires at least SQLite 3.38 or newer
§Examples
let json = json!({"a": 1, "c": 3});
let result = diesel::select(json_insert_1::<Json, Integer, _, _, _>(json, "$.b", 2))
.get_result::<serde_json::Value>(connection)?;
assert_eq!(json!({"a": 1, "b": 2, "c": 3}), result);
// A path that already exists is left unchanged.
let json = json!({"a": 1});
let result = diesel::select(json_insert_1::<Json, Integer, _, _, _>(json, "$.a", 99))
.get_result::<serde_json::Value>(connection)?;
assert_eq!(json!({"a": 1}), result);
// A path ending in "[#]" appends to an array.
let json = json!(['a', 'b', 'c']);
let result = diesel::select(json_insert_1::<Json, Text, _, _, _>(json, "$[#]", "d"))
.get_result::<serde_json::Value>(connection)?;
assert_eq!(json!(['a', 'b', 'c', 'd']), result);
let json = json!({"a": 1});
let result = diesel::select(
json_insert_2::<Json, Integer, Integer, _, _, _, _, _>(json, "$.b", 2, "$.c", 3),
)
.get_result::<serde_json::Value>(connection)?;
assert_eq!(json!({"a": 1, "b": 2, "c": 3}), result);
let json = json!({"a": 1});
let result = diesel::select(json_insert_0::<Json, _>(json))
.get_result::<serde_json::Value>(connection)?;
assert_eq!(json!({"a": 1}), result);
let result = diesel::select(json_insert_1::<Nullable<Json>, Integer, _, _, _>(None::<serde_json::Value>, "$.b", 1))
.get_result::<Option<serde_json::Value>>(connection)?;
assert_eq!(result, None);