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transformations:exportdb [2020/01/22 17:59]
dmitry
transformations:exportdb [2020/01/22 18:04] (current)
dmitry
Line 7: Line 7:
 Export will convert cell values only in the following cases: Export will convert cell values only in the following cases:
  
-  * Boolean cell to a numeric column ​1 or 0 will be exported +  * Boolean cell to a numeric column ​exported as (TRUE) ​or 0 (FALSE) 
-  * Numeric cell to a date or a datetime ​column - source number will be treated as an OADate and converted to a date or a datetime literal according to the format, supported by the target database +  * Numeric cell to a date or a date/​time ​column - the cell value is converted to a date or a datetime literal according to the SQL dialect of the target database 
-  * Any cell to a text column or a column of unknown type - will be exported as text +  * Any cell to a text column or a column of unknown type is exported as text literal 
-  * Error cell will be always exported as null+  * Error cells are always exported as NULL
  
-In all the other cases when cell type doesn’t match column type a NULL value will be exported.+In all the other cases when the cell type doesn’t match the target ​column type a NULL value is exported.
  
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 The operation is //atomic// meaning that it either successfully exports all rows, or nothing (in case of failure). 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 the [[sqlcommand|Database command]] action. Note that the operation effectively //appends// rows to existing ones. If you need to remove old data use the [[sqlcommand|Database command]] action.
  
-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 the [[sqlcommand|Database command]] action when exporting more than 1 million rows at once. +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 ​with the [[sqlcommand|Database command]] action when exporting more than 1 million rows at once. 
  
 ==See also== ==See also==
transformations/exportdb.txt · Last modified: 2020/01/22 18:04 by dmitry