Yep defo write out a csv file and then use mysqlimport or a 'Load data infile' statement for each table. If you do stick with DBI Inserts maybe try the inserts with multiple VALUES lists

INSERT INTO $table (field1,field2) VALUES (value1,value2),(values3,val
+ues4);
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From the mysql docs..

When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using a lot of INSERT statements. See section 13.1.5 LOAD DATA INFILE Syntax.

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