Author: timbo
Date: Tue Jun 2 03:05:32 2009
New Revision: 12804
Modified:
dbi/trunk/Changes
dbi/trunk/DBI.pm
Log:
Added docs form column_info()'s COLUMN_DEF value.
Clarified docs on stickyness of data type via bind_param().
Clarified docs on stickyness of data type via bind_col().
Modified: dbi/trunk/Changes
==============================================================================
--- dbi/trunk/Changes (original)
+++ dbi/trunk/Changes Tue Jun 2 03:05:32 2009
@@ -60,6 +60,10 @@
added f_schema attribute
table names case sensitive when quoted, insensitive when unquoted
+ Added docs form column_info()'s COLUMN_DEF value.
+ Clarified docs on stickyness of data type via bind_param().
+ Clarified docs on stickyness of data type via bind_col().
+
=head2 Changes in DBI 1.608 (svn r12742) 5th May 2009
Fixes to DBD::File (H.Merijn Brand)
Modified: dbi/trunk/DBI.pm
==============================================================================
--- dbi/trunk/DBI.pm (original)
+++ dbi/trunk/DBI.pm Tue Jun 2 03:05:32 2009
@@ -4611,7 +4611,23 @@
B<REMARKS>: A description of the column.
-B<COLUMN_DEF>: The default value of the column.
+B<COLUMN_DEF>: The default value of the column, in a format that can be used
+directly in an SQL statement.
+
+Note that this may be an expression and not simply the text used for the
+default value in the original CREATE TABLE statement. For example, given:
+
+ col1 char(30) default current_user -- a 'function'
+ col2 char(30) default 'string' -- a string literal
+
+where "current_user" is the name of a function, the corresponding C<COLUMN_DEF>
+values would be:
+
+ Database col1 col2
+ -------- ---- ----
+ Oracle: current_user 'string'
+ Postgres: "current_user"() 'string'::text
+ MS SQL: (user_name()) ('string')
B<SQL_DATA_TYPE>: The SQL data type.
@@ -5474,11 +5490,9 @@
See L</"DBI Constants"> for more information.
-The data type for a placeholder cannot be changed after the first
-C<bind_param> call. In fact the whole \%attr parameter is 'sticky'
-in the sense that a driver only needs to consider the \%attr parameter
-for the first call, for a given $sth and parameter. After that the driver
-may ignore the \%attr parameter for that placeholder.
+The data type for a placeholder cannot be changed after the first C<bind_param>
+call. The data type is said to be 'sticky'. Bind values passed to execute()
+are bound with the data type specified by earlier bind_param() calls, if any.
Perl only has string and number scalar data types. All database types
that aren't numbers are bound as strings and must be in a format the
@@ -6133,7 +6147,7 @@
native formatting the database would normally use.
There's no $var_to_bind in that example to emphasize the point
-that bind_col() works on the underlying column value and not just
+that bind_col() works on the underlying column and not just
a particular bound variable.
As a short-cut for the common case, the data type can be passed
@@ -6152,10 +6166,9 @@
See L</"DBI Constants"> for more information.
-The data type for a bind variable cannot be changed after the first
-C<bind_col> call. In fact the whole \%attr parameter is 'sticky'
-in the sense that a driver only needs to consider the \%attr parameter
-for the first call for a given $sth and column.
+Few drivers support specifying a data type via a C<bind_col> call (most will
+simply ignore the data type). Fewer still allow the data type to be altered
+once set.
The TYPE attribute for bind_col() was first specified in DBI 1.41.
