Revision 2393
Added by Aaron Marcuse-Kubitza about 12 years ago
| sql.py | ||
|---|---|---|
| 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=[]):
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|
| 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 = {}
|
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for table in tables: |
|
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for col in table_cols(db, table): |
|
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col = sql_gen.as_Col(col, table) |
|
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flatten_mapping[col] = sql_gen.Col(str(col), into) |
|
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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): |
|
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def flatten(db, into, joins, cols, limit=None, start=None, **kw_args):
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|
| 643 | 640 |
'''For params, see mk_flatten_mapping() |
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@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) |
|
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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) |
Also available in: Unified diff
sql.py: mk_flatten_mapping(), flatten(): Take list of cols to select instead of using all cols in all tables to join