Column expressions

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In SQL, column expressions are used :

In the select-list of a SELECT statement.

In the VALUES clause of an INSERT statement.

To the right of the = symbol in a SET clause of an UPDATE statement.

To the left and to the right of a comparison operator in a condition.

Syntax

A column expression is a column name or a literal value, optionally modified by a function call:

column-expression  ::=  function( { column | literal } )   column-operator column-expression   column-alias

 

column  ::=  {table-name|table-alias}.column-name

Literal number values must be passed unquoted. Literal character values and literal date values must be passed surrounded by single quotes.

A column expression is optionally modified by a function or a sequence of nested function calls. Column expressions are optionally passed to column operators, such as mathematical operators ( +, -, *, /), which expect a column-expression to their left and another to their right. A column expression optionally has a column alias.

 

 

collapseColumn names
collapseFunctions
collapseColumn operators
collapseColumn aliases

 

 

See also

Pseudo-columns

Host variables in SQL

Function calls

SQL conditions

SQL functions

RDBMS functions

Table aliases

SQL and the Rules Engine