Issues with asset transformation code

In working with CDF: Integrate, I am trying to transform the asset csv file using the following code: 

SELECT
concat('Ruby2001:',loc) as externalId,
IF(parent_loc='' OR parent_loc IS NULL, '', concat('Ruby2001:',parent_loc)) AS parentExternalId,

CAST(lastUpdatedTime AS STRING) AS name,

to_metadata(*) AS metadata,

description AS description,

2869936105026304 AS dataSetId
 
FROM `Ruby2001`.assets

However I keep getting this error message: 

Column 'parent_loc' does not exist. Did you mean one of the following? [z6eecbaa9603c4ee195055fe6aaeb89a3.loc, z6eecbaa9603c4ee195055fe6aaeb89a3.key, z6eecbaa9603c4ee195055fe6aaeb89a3.name, z6eecbaa9603c4ee195055fe6aaeb89a3.parent_loc,,, z6eecbaa9603c4ee195055fe6aaeb89a3.WMT_TAG_ID, z6eecbaa9603c4ee195055fe6aaeb89a3.description, z6eecbaa9603c4ee195055fe6aaeb89a3.WMT_SYSTEM_ID, z6eecbaa9603c4ee195055fe6aaeb89a3.lastUpdatedTime]; line 3 pos 3; 'Project [concat(Ruby2001:, loc#41009138) AS externalId#41009101, 'IF((('parent_loc = ) OR isnull('parent_loc)), , 'concat(Ruby2001:, 'parent_loc)) AS parentExternalId#41009102, cast(lastUpdatedTime#41009134 as string) AS name#41009103, map_from_arrays(array(key, lastUpdatedTime, WMT_SYSTEM_ID, WMT_TAG_ID, description, loc, name, parent_loc,,), array(cast(key#41009133 as string), cast(lastUpdatedTime#41009134 as string), cast(WMT_SYSTEM_ID#41009135 as string), cast(WMT_TAG_ID#41009136 as string), cast(description#41009137 as string), cast(loc#41009138 as string), cast(name#41009139 as string), cast(parent_loc,,#41009140 as string))) AS metadata#41009104, description#41009137 AS description#41009105, 2869936105026304 AS dataSetId#41009106L] +- SubqueryAlias z6eecbaa9603c4ee195055fe6aaeb89a3 +- View (`z6eecbaa9603c4ee195055fe6aaeb89a3`, [key#41009133,lastUpdatedTime#41009134,WMT_SYSTEM_ID#41009135,WMT_TAG_ID#41009136,description#41009137,loc#41009138,name#41009139,parent_loc,,#41009140]) +- Relation [key#41009133,lastUpdatedTime#41009134,WMT_SYSTEM_ID#41009135,WMT_TAG_ID#41009136,description#41009137,loc#41009138,name#41009139,parent_loc,,#41009140] RawTableRelation(db=Ruby2001, table=assets) | code: 400 | X-Request-ID: ce89d63f-1c78-97d2-9165-88b8621e92dd

I have checked the original asset csv and the variables are there but separated by a ‘;’ - should they be separated by ‘,’ instead? Thanks