A table name was specified in a select column, search condition or ORDER clause but this table name was not listed in the FROM clause.
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1. If a reference name was specified for a table name, use this reference name in the SQL statement.
2. If the FROM clause contains the specification of a table which does not belong to the current user, to this user's usergroup or to the database administrator, and which is not a system table, the owner must be specified for the table throughout the SQL statement.