ALTER TABLE nfs_op_fiscal_x_cst ADD COLUMN aliq_pis numeric (18,6);
ALTER TABLE nfs_op_fiscal_x_cst ADD COLUMN aliq_cofins numeric (18,6);

UPDATE nfs_op_fiscal_x_cst SET aliq_pis = 0 WHERE aliq_pis IS NULL;
UPDATE nfs_op_fiscal_x_cst SET aliq_cofins = 0 WHERE aliq_cofins IS NULL;

ALTER TABLE nfs_op_fiscal_x_cst ALTER COLUMN aliq_pis SET NOT NULL;
ALTER TABLE nfs_op_fiscal_x_cst ALTER COLUMN aliq_cofins SET NOT NULL;