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transformations:exportdb [2017/05/02 03:11] (current)
dmitry created
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 +===== Export into database table =====
 +Exports current dataset into database table which name is specified either explicitly or using a [[:​parameters|project parameter]]. The table must already exist. If the table doesn'​t exist it can be created using [[sqlcommand|Database command]] transformation prior to exporting data into it.
 +Export is performed using SQL INSERT statements by batches of 10 or 100 or 1000 rows. Exporting in bigger batches can be slightly faster on narrow tables (i.e. tables with few fields). For wide tables (i.e. table with hundreds of fields) or when fields contain long strings use smaller batches.
 +The operation is //atomic// meaning that it either successfully exports all rows, or nothing (in case of failure).
 +Note that the operation effectively //appends// rows to existing ones. If you need to remove old data use [[sqlcommand|Database command]] transformation.
 +Some databases have performance bottleneck for batches of SQL INSERT statements which may lead to slow performance (especially on wide tables). Consider using bulk load statements in [[sqlcommand|Database command]] transformation when exporting more than 1 million rows at once. See [[http://​​learn/​export-database.html|Tutorial:​ exporting data into a database table]]
transformations/exportdb.txt · Last modified: 2017/05/02 03:11 by dmitry