UpdateItem SET Expression Specification
SET-ACTION ::=
SET-ACTION-LHS '=' SET-ACTION-RHS
SET-ACTION-LHS ::= ATTRIBUTE-PATH
ATTRIBUTE-PATH ::=
parameter
| ATTRIBUTE-PATH '.' member-name
| ATTRIBUTE-PATH '[' int-expression ']'
| ATTRIBUTE-PATH '[' string-expression ']'
SET-ACTION-RHS ::= VALUE
VALUE ::=
OPERAND
| OPERAND '+' OPERAND
| OPERAND '-' OPERAND
OPERAND ::=
SET-FUNCTION
| ATTRIBUTE-PATH
| LITERAL
LITERAL ::=
| null-expression
| bool-expression
| binary-expression
| string-expression
| int-expression
| long-expression
| double-expression
| decimal-expression
| list-expression
| map-expression
| binary-set-expression
| string-set-expression
| int-set-expression
| long-set-expression
| double-set-expression
| decimal-set-expression
SET-FUNCTION ::=
IF-NOT-EXIST
| LIST-APPEND
IF-NOT-EXIST ::=
'if_not_exists' '(' ATTRIBUTE-PATH, VALUE ')'
LIST-APPEND ::=
'list_append' '(' OPERAND, OPERAND ')'