schemas/vegbien.sql: taxonlabel: taxonlabel_required_key constraint: Also allow taxonlabels with just a sourceaccessioncode, to support looking up parent taxonlabels using just their sourceaccessioncode (e.g. in NCBI)

mappings/VegCore-VegBIEN.csv: matched taxonlabel: Don't include taxonName in the concatenated taxonomicname. This also prevents the creation of the matched taxonlabel entirely when only the taxonName is provided.

mappings/VegCore-VegBIEN.csv: Don't create matched taxonlabel if taxonName was provided. This fixes a bug where an NCBI node was incorrectly pointing to a TNRS name, when the reference should only be the other way around. This may also fix the TNRS slowdown, if it was caused by circular matched_label_id references.

schemas/vegbien.sql: taxonlabel_2_set_canon_label_id_on_insert(): Fixed bug where also need to set canon_label_id based on matched_label_id here, not just in taxonlabel_2_set_canon_label_id_on_update(), because the matched_label_id could be specified when the taxonlabel is first created

schemas/vegbien.sql: taxonlabel_2_set_canon_label_id_on_*(): Fixed bug where need to use := instead of = to perform assignment of canon_label_id

schemas/tree_cross-links.sql: Updated for schema changes

schemas/vegbien.sql: taxonlabel_update_ancestors(): Include ancestors for both parent_id and matched_label_id rather than just one or the other. This avoids needing to delete existing ancestors for the parent_id when a matched_label_id is added and overrides it. This should reduce the TNRS import time if the slowdown was due to the need to delete parent_id ancestors when later adding a matched_label_id (which only occurs in a separate step in the TNRS datasource).

sql_io.py: put_table(): ensure_cond(): Fixed bug where test if any rows failed cond did not check if cur != None (which is the case when cond == sql_gen.true_expr) before checking cur.rowcount

sql_gen.py: simplify_expr(): Don't require () around NULL IS NULL and NULL IS NOT NULL because extra parentheses are not provided in index conditions, only in check constraint conditions

inputs/import.stats.xls: Updated import times. The TNRS import has slowed down significantly, possibly due to a bug in the autopopulation of the taxonlabel_relationship table when the input data contains cycles.