transformations:exportdb
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transformations:exportdb [2021/02/12 06:56] – dmitry | transformations:exportdb [2021/02/12 06:59] – dmitry | ||
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Exports the current dataset into the database table which name is specified either explicitly or using a [[: | Exports the current dataset into the database table which name is specified either explicitly or using a [[: | ||
- | 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 the target table. If you need to remove old data use the [[sqlcommand|Database command]] action. If you need to update rows, use the [[transformations: |
- | + | ||
- | Note that the operation effectively //appends// rows to existing ones. If you need to remove old data use the [[sqlcommand|Database command]] action. | + | |
===Performance=== | ===Performance=== | ||
Under the hood, the exporting 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. tables with hundreds of fields) or when columns contain long strings use smaller batches. | Under the hood, the exporting 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. tables with hundreds of fields) or when columns contain long strings use smaller batches. | ||
- | Some databases have a performance bottleneck for batches of SQL INSERT statements which may lead to slow performance (especially on wide tables). Consider using the [[transformations: | + | Some databases have a performance bottleneck for batches of SQL INSERT statements which may lead to slow performance (especially on wide tables). Consider using the [[transformations: |
===Data type conversion=== | ===Data type conversion=== | ||
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* [[http:// | * [[http:// | ||
* [[transformations: | * [[transformations: | ||
- | * [[transformations: | + | * [[transformations: |
+ | * [[transformations: |
transformations/exportdb.txt · Last modified: 2023/10/14 16:20 by craigt