LET
The LET
statement assigns values to variables.
Syntax
LET target = expr [,...]
- target is the name of the variable to be assigned.
- expr is any valid expression supported by the language.
Usage
The LET
statement
assigns a value to a variable, or a set of values to all members
of a RECORD
by using the .*
notation.
The runtime system applies data type conversion rules if the data type of expression does not correspond to the data type of target.
When assigning a numeric of date/time value to a character string variable, the values are formatted for display (for example, the numeric data is right-aligned).
When specifying a comma-separated list of expressions for the
right operand, the LET
statement concatenates
all expressions together. Unlike the ||
operator,
if an expression in the comma-separated list evaluates to
NULL
, the concatenation result will not be null,
except if all expressions to the right of the equal sign are
null.
The target variable can be record followed by dot +
star (record.*
), to reference all record
members of the record. In this case, the right operand must also be
a record using this notation, and all members will be assigned
individually.
Variables defined with a complex data type
(like TEXT
or BYTE
) can
only be assigned to NULL
.
Example
SCHEMA stores
MAIN
DEFINE c1, c2 RECORD LIKE customer.*
-- Single variable assignment
LET c1.customer_num = 123
-- Complete RECORD assignment
LET c1.* = c2.*
END MAIN