| 614 |
614 |
return list(col_names(select(db, table, limit=0, order_by=None,
|
| 615 |
615 |
recover=recover)))
|
| 616 |
616 |
|
| 617 |
|
def mk_flatten_mapping(db, into, tables, preserve=[]):
|
|
617 |
def mk_flatten_mapping(db, into, cols, preserve=[]):
|
| 618 |
618 |
'''Creates a mapping from original column names (which may have collisions)
|
| 619 |
619 |
to names that will be distinct among the given tables.
|
| 620 |
620 |
This is meant to be used for several tables that are being joined together.
|
| ... | ... | |
| 629 |
629 |
changed for all columns at once
|
| 630 |
630 |
'''
|
| 631 |
631 |
flatten_mapping = {}
|
| 632 |
|
for table in tables:
|
| 633 |
|
for col in table_cols(db, table):
|
| 634 |
|
col = sql_gen.as_Col(col, table)
|
| 635 |
|
flatten_mapping[col] = sql_gen.Col(str(col), into)
|
|
632 |
for col in cols: flatten_mapping[col] = sql_gen.Col(str(col), into)
|
| 636 |
633 |
for col in preserve:
|
| 637 |
634 |
orig_col = copy.copy(col)
|
| 638 |
635 |
col.table = into
|
| 639 |
636 |
flatten_mapping[orig_col] = col
|
| 640 |
637 |
return flatten_mapping
|
| 641 |
638 |
|
| 642 |
|
def flatten(db, into, joins, limit=None, start=None, **kw_args):
|
|
639 |
def flatten(db, into, joins, cols, limit=None, start=None, **kw_args):
|
| 643 |
640 |
'''For params, see mk_flatten_mapping()
|
| 644 |
641 |
@return See return value of mk_flatten_mapping()
|
| 645 |
642 |
'''
|
| 646 |
|
tables = joins[:1]+[v.table for v in joins[1:]]
|
| 647 |
|
mapping = mk_flatten_mapping(db, into, tables, **kw_args)
|
|
643 |
mapping = mk_flatten_mapping(db, into, cols, **kw_args)
|
| 648 |
644 |
cols = [sql_gen.NamedCol(new.name, old) for old, new in mapping.iteritems()]
|
| 649 |
645 |
run_query_into(db, *mk_select(db, joins, cols, limit=limit, start=start),
|
| 650 |
646 |
into=into)
|
sql.py: mk_flatten_mapping(), flatten(): Take list of cols to select instead of using all cols in all tables to join