18.3.21 QSC - query selection criteria (2A.3.61)

HL7 Component Table - QSC - Query Selection Criteria

Core Framework									Base Standard Profile
Seq#	Description	Interpretation	Flags	Cardinality	Length	C.LEN	Vocabulary	Data Type	Implement	Cardinality	Vocabulary
QSC
1	Segment Field Name			[1..1]				ST	SHALL
2	Relational Operator			[0..1]			relationalOperator (CD VS)	ID			(CS)
3	Value			[0..1]				ST
4	Relational Conjunction			[0..1]			relationalConjunction (CD VS)	ID			(CS)

Definition: This field indicates the conditions that qualify the rows to be returned in the query response.

Example:

|@PID.5.1^EQ^EVANS|

18.3.21.1 Segment Field Name (ST) (2A.3.61.0)

Definition: The name of the field that is participating as a qualifier (usually the "key"). Refer to Section 2.A.59.1, “Segment Field Name (ST),” for segment field name conventions.

18.3.21.2 Relational Operator (ID) (2A.3.61.1)

Definition: Refer to HL7 Table 0209 - Relational Operator for valid values.

18.3.21.3 Value (ST) (2A.3.61.2)

Definition: The value to which the field will be compared.

18.3.21.4 Relational Conjunction (ID) (2A.3.61.3)

Definition: Refer to HL7 Table 0210 - Relational Conjunction for valid values. The relational conjunction is defined as follows: If more than one comparison is to be made to select qualifying rows, a conjunction relates this repetition of the field to the next.

• When applied to strings, the relational operators LT, GT, LE, and GE imply an alphabetic comparison.

• A "generic" comparison selects a record for inclusion in the response when the beginning of the designated field matches the select string.

• Where a repeating field is specified as an operand, a match on any instance of that field qualifies the row for inclusion in the response message.

• AND takes precedence over OR. More sophisticated precedence rules require that the query be expressed as an embedded query language message or a stored procedure query message (see Chapter 5, "Query").