DDC-736: Nasty ordering issue with fetch-joins

[doctrinebot]

Jira issue originally created by user romanb:

Will not work correctly:

select c, ca from Cart ca join ca.customer c

Works correctly:

select ca, c from Cart ca join ca.customer c

In the first case the ordering of the DQL aliases causes associations to be skipped during hydration.

[doctrinebot]

• is referenced by DDC-915: Breaks with Fixing Identification Variables and SQL Walkers
• is referenced by DDC-925: Breaks with Fixing Identification Variables and SQL Walkers - 2

[doctrinebot]

Comment created by romanb:

Scheduling for RC1.

[doctrinebot]

Comment created by mitmaro:

If anyone is getting issues with missing or incorrectly ordered relations it may be caused by this bug.

Would it be possible to put a note in the documentation to ensure the order of the select clause must match that of the joins. I just spent 2 days trying to figure out why the data being returned was incorrect.

[doctrinebot]

Comment created by @beberlei:

Patch that solves this problem. What does it do?

Two additional instance variables are needed, one for the order of the AliasIdentificationVariables and one for a IdentVariable => SelectExpression lookup map.

Inside parse() a reordering is done right before the SQL Walkers are created. This is only done if there is more than one Identification variable in the select expressions, otherwise its not necessary.

The reordering iterates in order of the alias identification variables, grabs the expression from the select expressions and appends it to them. This way it is guaranteed that the expressions are ordered correctly.

SELECT a, b, c.foo, count(d.bar) FROM B b JOIN b.a a JOIN ...

becomes:

SELECT c.foo, count(d.bar), b, a FROM ...

Roman do you think this is viable? See the patch for more details ;)

[doctrinebot]

Comment created by romanb:

Attached simplified patch.

[doctrinebot]

Comment created by @beberlei:

Fixed.

[doctrinebot]

Issue was closed with resolution "Fixed"

[doctrinebot]

Comment created by hype:

I think that this patch breaks modifying the select clause in custom tree walkers because walking the select clause will be done after the $_identVariableExpressions array is populated. Reordering the identification variables will then override the modified select clause.

[doctrinebot]

Imported 3 attachments from Jira into https://gist.github.com/044a2dc627a11e5c3a9e

• 10846_DDC736Test.php
• 10857_ddc736.patch
• 10860_ddc736-simplified.patch