Parameters

Positional Single

A lone ? resolves to the first list element.

SQL

select ?;

Result

[
  42
]

Each ?

Each ? consumes the next list slot in source order.

SQL

select [?, ?, ?];

Result

[
  [ 1, 2, 3 ]
]

Positional String

A string parameter.

SQL

select ?;

Result

[
  "hello"
]

Positional null

A null parameter.

SQL

select ?;

Result

[
  null
]

Parameters Compose

Parameters compose inside an expression.

SQL

select ? + ?;

Result

[
  30
]

$1 Is

$1 is the first (1-based) list element.

SQL

select $1;

Result

[
  7
]

The Same

The same index may be referenced more than once.

SQL

select [$1, $1, $2];

Result

[
  [ 9, 9, 8 ]
]

Numbered References

Numbered references pick by index, not by appearance.

SQL

select [$2, $1];

Result

[
  [ "b", "a" ]
]

The First

The first ? and $1 both resolve to list[0].

SQL

select [?, $1];

Result

[
  [ 5, 5 ]
]

Named Single

A named parameter resolves from the map.

SQL

select $foo;

Result

[
  99
]

Several Named Parameters

Several named parameters.

SQL

select [$a, $b];

Result

[
  [ 1, 2 ]
]

Where Positional

A parameter as a where-clause operand.

SQL

create table T;

insert into T ({"x": 1}, {"x": 2}, {"x": 3});

select * from T where T.x > ?;

Result

[
  { "x": 2 },
  { "x": 3 }
]

Where Named

A named parameter in a Where clause.

SQL

create table T;

insert into T ({"x": 1}, {"x": 2});

select * from T where T.x = $val;

Result

[
  { "x": 2 }
]

Keyed Get Positional

A parameter as a keyed-table index (substituted to a literal key).

SQL

create table t (id int);

insert into t ({"id": 1, "v": "a"}, {"id": 2, "v": "b"});

select t[?];

Result

[
  { "id": 2, "v": "b" }
]

? With

? with too few list elements is a bind error.

SQL

select [?, ?];

Expected error: static

$2 With

$2 with a one-element list is a bind error.

SQL

select $2;

Expected error: static

An Absent

An absent named key is a bind error.

SQL

select $foo;

Expected error: static

$0 Is

$0 is out of range (numbering is 1-based).

SQL

select $0;

Expected error: static

Numbered Overflow

A numbered index past u32 is a static bind error, not an opaque lexer error.

SQL

select $4294967296;

Expected error: static

No Parameters Supplied

A placeholder with no parameters at all is a bind error.

SQL

select ?;

Expected error: static