Column Reference (SQL)

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The SQL Column Reference is a reference to a column in a table or query result.


column-reference ::=
  identifier [ { . identifier } ]


Column references can consist of a single identifier, or an identifier chain. You can use an identifier chain to resolve ambiguities when a query refers to multiple tables.


  1. Single identifier column references:
    Select FullName, Value, Units
    From TagDataPointAnalog
  2. Two part column identifiers using a correlation name:
    Select "T".FullName, "T".Value, "T".Units
    From TagDataPointAnalog "T"
  3. Three part column identifiers using a schema and table name to qualify the column names:
    Select CommonBase.TagDataPointAnalog.FullName, CommonBase.TagDataPointAnalog.Value, CommonBase.TagDataPointAnalog.Units
    From CommonBase.TagDataPointAnalog

Further Information

Value Expressions (SQL)

To learn more about SQL scalar value expressions.

Fernhill SCADA Structured Query Language (SQL)

To learn more about the SQL features in Fernhill SCADA.


For the meaning of terms used in Fernhill SCADA.