Assignment rules for host variables in SQL statements

SQL values are assigned to host variables during the running of FETCH, SELECT INTO, SET, and VALUES INTO statements. SQL values are assigned from host variables during the running of INSERT, UPDATE, and CALL statements.

All assignment operations observe the following rules:

Numbers and strings are compatible:
- Numbers can be assigned to character or graphic string columns or host variables.
- Character and graphic strings can be assigned to numeric columns or numeric host variables.
All character and DBCS graphic strings are compatible with UCS-2 and UTF-16 graphic columns if conversion is supported between the CCSIDs. All graphic strings are compatible if the CCSIDs are compatible. All numeric values are compatible. Conversions are performed by SQL whenever necessary. All character and DBCS graphic strings are compatible with UCS-2 and UTF-16 graphic columns for assignment operations, if conversion is supported between the CCSIDs. For the CALL statement, character and DBCS graphic parameters are compatible with UCS-2 and UTF-16 parameters if conversion is supported.
Binary strings are only compatible with binary strings.
A null value cannot be assigned to a host variable that does not have an associated indicator variable.
Different types of date/time values are not compatible. Dates are only compatible with dates or string representations of dates; times are only compatible with times or string representations of times; and timestamps are only compatible with timestamps or string representations of timestamps.
A date can be assigned only to a date column, a character column, a DBCS-open or DBCS-either column or variable, or a character variable. The insert or update value of a date column must be a date or a string representation of a date. A DBCS-open or DBCS-either variable is a variable that was declared in the host language by including the definition of an externally described file. DBCS-open variables are also declared if the job CCSID indicates MIXED data, or the DECLARE VARIABLE statement is used and a MIXED CCSID or the FOR MIXED DATA clause is specified.

A time can be assigned only to a time column, a character column, a DBCS-open or DBCS-either column or variable, or a character variable. The insert or update value of a time column must be a time or a string representation of a time.

A timestamp can be assigned only to a timestamp column, a character column, a DBCS-open or DBCS-either column or variable, or a character variable. The insert or update value of a timestamp column must be a timestamp or a string representation of a timestamp.

Rules for string assignment of host variables in SQL statements
This topic introduces rules regarding character string assignment.
Rules for CCSIDs of host variables in SQL statements
CCSIDs must be considered when you assign one character or graphic value to another. This includes the assignment of host variables. The database manager uses a common set of system services for converting SBCS data, DBCS data, MIXED data, and graphic data.
Rules for numeric assignment of host variables in SQL statements
Rules regarding numeric assignment are as follows.
Rules for date, time, and timestamp assignment of host variables in SQL statements
When a date is assigned to a host variable, the date is converted to the string representation specified by the DATFMT and DATSEP parameters of the CRTSQLxxx command.

Parent topic: Use host variables in SQL statements

Related information

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