Item Method Operators in QBE

Item Method Operators act on a JSON field, transform it’s value and then compare it to the comparison value.

The item method operators are analogous to the SQL operators or functions. Oracle AI Database for GraphQL supports the following item method QBE operators:

GraphQL QBE Item Method Operator	Equivalent SQL Operator
_abs	To get the absolute value of a field. Equivalent to ABS in SQL.
_boolean	To typecast to boolean. Equivalent of TO_BOOLEAN in SQL.
_number	To typecast to a number. Equivalent of TO_NUMBER in SQL.
_double	To typecast to binary_double. Equivalent of TO_BINARY_DOUBLE in SQL.
_string	To typecast to char. Equivalent of TO_CHAR in SQL.
_date	To type cast to date. Equivalent of TO_DATE in SQL.
_timestamp	To type cast to timestamp. Equivalent of TO_TIMESTAMP in SQL.
_ceiling	To get the ceil value of a number. Equivalent of CEIL in SQL.
_floor	To get the floor value of a number. Equivalent of FLOOR in SQL.
_lower	To convert the string into lower case. Equivalent of LOWER in SQL.
_upper	To convert the string into upper case. Equivalent of UPPER in SQL.
_length	To get the length of the value. Equivalent of LENGTH in SQL.
_size	To get the size of data type. Equivalent of VSIZE in SQL.

• STRING QBE Operator
  Learn to use _string QBE operator to filter specific data from the car racing dataset through simple examples.

• LOWER and UPPER QBE Operators
  Learn to use QBE operators _upper, and _lower to filter specific data from the car racing dataset through simple examples.

• LENGTH QBE Operator
  Learn to use the _length QBE operator to filter specific data from the car racing dataset through simple examples.