Revision 2353
Added by Aaron Marcuse-Kubitza over 12 years ago
| sql_gen.py | ||
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| 174 | 174 |
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| 175 | 175 |
join_same = object() # tells Join the left and right columns have the same name |
| 176 | 176 |
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# Tells Join the left and right columns have the same name and are never NULL |
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join_same_not_null = object() |
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filter_out = object() # tells Join to filter out rows that match the join |
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class Join(Code): |
| ... | ... | |
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''' |
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@param mapping dict(right_table_col=left_table_col, ...) |
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* if left_table_col is join_same: left_table_col = right_table_col |
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* Note that right_table_col must be a string |
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* if left_table_col is join_same_not_null: |
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left_table_col = right_table_col and both have NOT NULL constraint |
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* Note that right_table_col must be a string |
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@param type_ None (for plain join)|str (e.g. 'LEFT')|filter_out |
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* filter_out: equivalent to 'LEFT' with the query filtered by |
| 186 | 193 |
`table_pkey IS NULL` (indicating no match) |
| ... | ... | |
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self.type_ = type_ |
| 194 | 201 |
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def to_str(self, db, left_table): |
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# Switch order (left_table is on the right in the comparison) |
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right_table = left_table |
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left_table = self.table # note left_table is reassigned |
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def join(entry): |
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'''Parses non-USING joins''' |
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right_table_col, left_table_col = entry |
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# Note that right_table_col is on the left in the comparison |
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| 200 | 210 |
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# Switch order (right_table_col is on the left in the comparison) |
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left = right_table_col |
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right = left_table_col |
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# Parse special values |
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if left_table_col is join_same: left_table_col = right_table_col |
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if right is join_same: right = left |
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elif right is join_same_not_null: |
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right = CompareCond(as_Col(left, right_table), '~=') |
|
| 203 | 219 |
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cond = as_ValueCond(left_table_col, left_table)
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return cond.to_str(db, as_Col(right_table_col, self.table))
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right = as_ValueCond(right, right_table)
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return right.to_str(db, as_Col(left, left_table))
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| 206 | 222 |
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# Create join condition |
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type_ = self.type_ |
| ... | ... | |
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if type_ is filter_out: type_ = 'LEFT' |
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str_ = '' |
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if type_ != None: str_ += type_+' ' |
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str_ += 'JOIN '+self.table.to_str(db)+' '+join_cond
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str_ += 'JOIN '+left_table.to_str(db)+' '+join_cond
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| 222 | 238 |
return str_ |
| 223 | 239 |
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def __str__(self): return self.to_str(mockDb, '') |
Also available in: Unified diff
sql_gen.py: Join: Added join_same_not_null. to_str(): Refactored to switch order of left and right tables and cols because left_table is on the right in the comparison, and using the sides of the comparison instead of the sides of the join makes the code clearer.