dbbase.column_types.WriteOnlyColumn.in_

WriteOnlyColumn.in_(other)

Implement the in operator.

In a column context, produces the clause column IN <other>.

The given parameter other may be:

• A list of literal values, e.g.:

  stmt.where(column.in_([1, 2, 3]))
  

  In this calling form, the list of items is converted to a set of bound parameters the same length as the list given:

  WHERE COL IN (?, ?, ?)
  

• A list of tuples may be provided if the comparison is against a tuple_() containing multiple expressions:

  from sqlalchemy import tuple_
  stmt.where(tuple_(col1, col2).in_([(1, 10), (2, 20), (3, 30)]))
  

• An empty list, e.g.:

  stmt.where(column.in_([]))
  

  In this calling form, the expression renders a “false” expression, e.g.:

  WHERE 1 != 1
  

  This “false” expression has historically had different behaviors in older SQLAlchemy versions, see :paramref:`_sa.create_engine.empty_in_strategy` for behavioral options.

  Changed in version 1.2: simplified the behavior of “empty in” expressions

• A bound parameter, e.g. bindparam(), may be used if it includes the :paramref:`.bindparam.expanding` flag:

  stmt.where(column.in_(bindparam('value', expanding=True)))
  

  In this calling form, the expression renders a special non-SQL placeholder expression that looks like:

  WHERE COL IN ([EXPANDING_value])
  

  This placeholder expression is intercepted at statement execution time to be converted into the variable number of bound parameter form illustrated earlier. If the statement were executed as:

  connection.execute(stmt, {"value": [1, 2, 3]})
  

  The database would be passed a bound parameter for each value:

  WHERE COL IN (?, ?, ?)
  

  New in version 1.2: added “expanding” bound parameters

  If an empty list is passed, a special “empty list” expression, which is specific to the database in use, is rendered. On SQLite this would be:

  WHERE COL IN (SELECT 1 FROM (SELECT 1) WHERE 1!=1)
  

  New in version 1.3: “expanding” bound parameters now support empty lists

• a _expression.select() construct, which is usually a correlated scalar select:

  stmt.where(
      column.in_(
          select([othertable.c.y]).
          where(table.c.x == othertable.c.x)
      )
  )
  

  In this calling form, ColumnOperators.in_() renders as given:

  WHERE COL IN (SELECT othertable.y
  FROM othertable WHERE othertable.x = table.x)
  

Parameters

other – a list of literals, a _expression.select() construct, or a bindparam() construct that includes the :paramref:`.bindparam.expanding` flag set to True.