2015-10-05 0:08 GMT+02:00 Marko Tiikkaja <marko@joh.to>:
Hi,
In the past I've found the error message in cases such as this somewhat less helpful than it could be:
=# CREATE TABLE qqq (a int); =# CREATE UNIQUE INDEX IF NOT EXISTS qqq_a_idx ON qqq(a); =# ALTER TABLE qqq ALTER COLUMN a TYPE json USING NULL; ERROR: data type json has no default operator class for access method "btree" HINT: You must specify an operator class for the index or define a default operator class for the data type.
The attached patch adds a CONTEXT line to index and constraint rebuilds, e.g: