Assignment semantics in a federated system - examples

The following table shows several examples of the application of federated assignment semantics in queries given a local type and remote type.

Table 1. Examples of assignment semantics
Local type Remote type Your query Generated remote query
FLOAT INTEGER set c1=123.23 set c1=INTEGER(123.23)
INTEGER FLOAT set c1=123.23 set c1=INTEGER(123.23)
FLOAT INTEGER set c1=123 set c1=123
CHAR(10) CHAR(20) set c1='123' set c1='123' ('123' has a type VARCHAR(3) and it's the shortest of all)
CHAR(10) CHAR(20) set c1=char23col set c1=CHAR(char23col, 10)
CHAR(10) CHAR(20) set c1=expr1
  • set c1=expr1 -- if expr1 returns char(n) n<= 10
  • set c1=CHAR(expr1, 10) if expr1 returns char(n) n>10
TIMESTAMP DATE set c1= current timestamp set c1=DATE(current timestamp)