--- a/tablecopy.py Thu May 10 08:42:21 2012 +0200
+++ b/tablecopy.py Fri May 11 14:16:36 2012 +0200
@@ -1,11 +1,16 @@
#!/usr/bin/env python3.2
#
-# Copy data from one table to another table with same schema.
+# Copy data between tables with same table schema.
+#
+# Can copy multiple tables in one run.
+# Sorts the tables according to references.
+#
+# This may be used instead of dump/restore.
#
import io
-from pgtoolkit import toolbase, pgmanager, pgdatacopy
+from pgtoolkit import toolbase, pgmanager, pgbrowser, pgdatacopy
from pgtoolkit.progresswrapper import ProgressWrapper
@@ -15,40 +20,83 @@
self.parser.add_argument('-n', '--no-action', dest='noaction', action='store_true',
help="Do nothing, just print tables to be copied. Useful in combination with --regex.")
+ self.parser.add_argument('--no-sort', dest='nosort', action='store_true',
+ help="Do not sort. By default, tables are sorted by foreign key references.")
self.init()
def main(self):
- srcconn = self.pgm.get_conn('src')
- dstconn = self.pgm.get_conn('dst')
+ self.srcconn = self.pgm.get_conn('src')
+ self.dstconn = self.pgm.get_conn('dst')
- dc = pgdatacopy.PgDataCopy(srcconn, dstconn)
+ dc = pgdatacopy.PgDataCopy(self.srcconn, self.dstconn)
- for srcschema, srctable, dstschema, dsttable in self.tables():
- print('Copying [%s] %s.%s --> [%s] %s.%s' % (
- self.args.src, srcschema, srctable,
- self.args.dst, dstschema, dsttable))
+ if self.args.nosort:
+ for table in self.tables():
+ self.copy_table(dc, *table)
+ else:
+ # sort tables with respect to references
+ details = dict()
+ pending = set()
+ references = dict()
- if self.args.noaction:
- continue
+ # build list of all table to be copied (pending) and references map
+ for table in self.tables():
+ srcschema, srctable, dstschema, dsttable = table
+ name = dstschema + '.' + dsttable
+ details[name] = table
+ pending.add(name)
+ references[name] = self.get_references(dstschema, dsttable)
- dc.set_source(srctable, srcschema)
- dc.set_destination(dsttable, dstschema)
+ # copy files with fulfilled references, repeat until all done
+ while pending:
+ for name in list(pending):
+ ok = True
+ for ref in references[name]:
+ if ref in pending:
+ ok = False
+ if ok:
+ table = details[name]
+ self.copy_table(dc, *table)
+ pending.remove(name)
+
+ def get_references(self, schema, table):
+ browser = pgbrowser.PgBrowser(self.dstconn)
+ cons = browser.list_constraints(table, schema)
+ return [con['fschema'] + '.' + con['fname'] for con in cons if con['type'] == 'f']
+
+ def copy_table(self, dc, srcschema, srctable, dstschema, dsttable):
+ print('Copying [%s] %s.%s --> [%s] %s.%s' % (
+ self.args.src, srcschema, srctable,
+ self.args.dst, dstschema, dsttable))
- dc.check()
+ if self.args.noaction:
+ return
- buf = io.BytesIO()
- wrapped = ProgressWrapper(buf)
- dc.read(wrapped)
- data = buf.getvalue()
- buf.close()
-
- buf = io.BytesIO(data)
- wrapped = ProgressWrapper(buf, len(data))
- dc.write(wrapped)
- buf.close()
+ dc.set_source(srctable, srcschema)
+ dc.set_destination(dsttable, dstschema)
+
+ try:
+ dc.check()
+ except pgdatacopy.TargetNotEmptyError as e:
+ print(' - error:', str(e))
+ return
- dc.analyze()
+ print(' - read ')
+ buf = io.BytesIO()
+ wrapped = ProgressWrapper(buf)
+ dc.read(wrapped)
+ data = buf.getvalue()
+ buf.close()
+
+ print(' - write ')
+ buf = io.BytesIO(data)
+ wrapped = ProgressWrapper(buf, len(data))
+ dc.write(wrapped)
+ buf.close()
+
+ print(' - analyze ')
+ dc.analyze()
tool = TableCopyTool()