Beam ZetaSQL operators
Operators are represented by special characters or keywords; they do not use function call syntax. An operator manipulates any number of data inputs, also called operands, and returns a result.
Common conventions:
 Unless otherwise specified, all operators return
NULL
when one of the operands isNULL
.
The following table lists all supported operators from highest to lowest precedence. Precedence determines the order in which operators will be evaluated within a statement.
Order of Precedence  Operator  Input Data Types  Name  Operator Arity 

1  .  STRUCT 
Member field access operator  Binary 
[ ]  ARRAY  Array position. Must be used with OFFSET or ORDINAL&mdash.  Binary  
2    All numeric types  Unary minus  Unary 
3  *  All numeric types  Multiplication  Binary 
/  All numeric types  Division  Binary  
4  +  All numeric types  Addition  Binary 
  All numeric types  Subtraction  Binary  
5 (Comparison Operators)  =  Any comparable type. See Data Types for a complete list.  Equal  Binary 
<  Any comparable type. See Data Types for a complete list.  Less than  Binary  
>  Any comparable type. See Data Types for a complete list.  Greater than  Binary  
<=  Any comparable type. See Data Types for a complete list.  Less than or equal to  Binary  
>=  Any comparable type. See Data Types for a complete list.  Greater than or equal to  Binary  
!=, <>  Any comparable type. See Data Types for a complete list.  Not equal  Binary  
[NOT] LIKE  STRING and byte  Value does [not] match the pattern specified  Binary  
[NOT] BETWEEN  Any comparable types. See Data Types for list.  Value is [not] within the range specified  Binary  
[NOT] IN  Any comparable types. See Data Types for list.  Value is [not] in the set of values specified  Binary  
IS [NOT] NULL 
All  Value is [not] NULL 
Unary  
IS [NOT] TRUE  BOOL  Value is [not] TRUE.  Unary  
IS [NOT] FALSE  BOOL  Value is [not] FALSE.  Unary  
6  NOT  BOOL  Logical NOT  Unary 
7  AND  BOOL  Logical AND  Binary 
8  OR  BOOL  Logical OR  Binary 
Operators with the same precedence are left associative. This means that those operators are grouped together starting from the left and moving right. For example, the expression:
x AND y AND z
is interpreted as
( ( x AND y ) AND z )
The expression:
x * y / z
is interpreted as:
( ( x * y ) / z )
All comparison operators have the same priority and are grouped using left associativity. However, comparison operators are not associative. As a result, it is recommended that you use parentheses to improve readability and ensure expressions are resolved as desired. For example:
(x < y) IS FALSE
is recommended over:
x < y IS FALSE
Element access operators
Operator  Syntax  Input Data Types  Result Data Type  Description 

.  expression.fieldname1...  STRUCT 
Type T stored in fieldname1  Dot operator. Can be used to access nested fields, e.g.expression.fieldname1.fieldname2... 
[ ]  array_expression [position_keyword (int_expression ) ]  See ARRAY Functions.  Type T stored in ARRAY  position_keyword is either OFFSET or ORDINAL. 
Arithmetic operators
All arithmetic operators accept input of numeric type T, and the result type has type T unless otherwise indicated in the description below:
Name  Syntax 

Addition  X + Y 
Subtraction  X  Y 
Multiplication  X * Y 
Division  X / Y 
Unary Minus   X 
Result types for Addition and Multiplication:
INT64  FLOAT64  

INT64  INT64  FLOAT64 
FLOAT64  FLOAT64  FLOAT64 
Result types for Subtraction:
INT64  FLOAT64  

INT64  INT64  FLOAT64 
FLOAT64  FLOAT64  FLOAT64 
Result types for Division:
INT64  FLOAT64  

INT64  FLOAT64  FLOAT64 
FLOAT64  FLOAT64  FLOAT64 
Result types for Unary Minus:
Input Data Type  Result Data Type 

INT64  INT64 
FLOAT64  FLOAT64 
Logical operators
All logical operators allow only BOOL input.
Name  Syntax  Description 

Logical NOT  NOT X  Returns FALSE if input is TRUE. Returns TRUE if input is FALSE. Returns NULL
otherwise. 
Logical AND  X AND Y  Returns FALSE if at least one input is FALSE. Returns TRUE if both X and Y
are TRUE. Returns NULL otherwise. 
Logical OR  X OR Y  Returns FALSE if both X and Y are FALSE. Returns TRUE if at least one input
is TRUE. Returns NULL otherwise. 
Comparison operators
Comparisons always return BOOL. Comparisons generally require both operands to be of the same type. If operands are of different types, and if Cloud Dataflow SQL can convert the values of those types to a common type without loss of precision, Cloud Dataflow SQL will generally coerce them to that common type for the comparison; Cloud Dataflow SQL will generally coerce literals to the type of nonliterals, where present. Comparable data types are defined in Data Types.
STRUCTs support only 4 comparison operators: equal (=), not equal (!= and <>), and IN.
The following rules apply when comparing these data types:

 FLOAT64
 All comparisons with NaN return FALSE,
except for
!=
and<>
, which return TRUE.
 BOOL: FALSE is less than TRUE.
 STRING: Strings are compared codepointbycodepoint, which means that canonically equivalent strings are only guaranteed to compare as equal if they have been normalized first.
NULL
: The convention holds here: any operation with aNULL
input returnsNULL
.
Name  Syntax  Description 

Less Than  X < Y  Returns TRUE if X is less than Y. 
Less Than or Equal To  X <= Y  Returns TRUE if X is less than or equal to Y. 
Greater Than  X > Y  Returns TRUE if X is greater than Y. 
Greater Than or Equal To  X >= Y  Returns TRUE if X is greater than or equal to Y. 
Equal  X = Y  Returns TRUE if X is equal to Y. 
Not Equal  X != Y X <> Y 
Returns TRUE if X is not equal to Y. 
BETWEEN  X [NOT] BETWEEN Y AND Z  Returns TRUE if X is [not] within the range specified. The result of "X BETWEEN Y AND Z" is equivalent to "Y <= X AND X <= Z" but X is evaluated only once in the former. 
LIKE  X [NOT] LIKE Y  Checks if the STRING in the first operand X
matches a pattern specified by the second operand Y. Expressions can contain
these characters:

IN  Multiple  see below  Returns FALSE if the right operand is empty. Returns NULL if the left
operand is NULL . Returns TRUE or NULL , never FALSE, if the right operand
contains NULL . Arguments on either side of IN are general expressions. Neither
operand is required to be a literal, although using a literal on the right is
most common. X is evaluated only once. 
When testing values that have a STRUCT data type for
equality, itâ€™s possible that one or more fields are NULL
. In such cases:
 If all nonNULL field values are equal, the comparison returns NULL.
 If any nonNULL field values are not equal, the comparison returns false.
The following table demonstrates how STRUCT data
types are compared when they have fields that are NULL
valued.
Struct1  Struct2  Struct1 = Struct2 

STRUCT(1, NULL) 
STRUCT(1, NULL) 
NULL 
STRUCT(1, NULL) 
STRUCT(2, NULL) 
FALSE 
STRUCT(1,2) 
STRUCT(1, NULL) 
NULL 
IS operators
IS operators return TRUE or FALSE for the condition they are testing. They never
return NULL
, even for NULL
inputs. If NOT is present, the output BOOL value
is inverted.
Function Syntax  Input Data Type  Result Data Type  Description 

X IS [NOT] NULL 
Any value type  BOOL  Returns TRUE if the operand X evaluates to NULL , and returns FALSE
otherwise. 
X IS [NOT] TRUE 
BOOL  BOOL  Returns TRUE if the BOOL operand evaluates to TRUE. Returns FALSE otherwise. 
X IS [NOT] FALSE 
BOOL  BOOL  Returns TRUE if the BOOL operand evaluates to FALSE. Returns FALSE otherwise. 