# Conversion to UNKNOWN in a query

**URL:** <https://forum.inductiveautomation.com/t/conversion-to-unknown-in-a-query/17155>\
**Category:** Ignition\
**Created:** [February 27, 2018, 3:49pm UTC](https://forum.inductiveautomation.com/t/conversion-to-unknown-in-a-query/17155 "2018-02-27T15:49:33Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![patrick.garceau](https://avatars.discourse-cdn.com/v4/letter/p/76d3ee/32.png) [@patrick.garceau](https://forum.inductiveautomation.com/u/patrick.garceau)\
**Post date:** [February 27, 2018, 3:49pm UTC](https://forum.inductiveautomation.com/t/conversion-to-unknown-in-a-query/17155/1 "2018-02-27T15:49:33Z")

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Caused by: java.lang.Exception: Error executing system.db.runPrepUpdate(insert into aws\_log(tagpath,lasttime) Values(?,?), [1\_i1-1\_i10/1\_i10, 1517461200000], Ignition, , false, false)  
Caused by: com.inductiveautomation.ignition.client.gateway\_interface.GatewayException: SQL error for “insert into aws\_log(tagpath,lasttime) Values(?,?)”: The conversion from UNKNOWN to UNKNOWN is unsupported.

Testing is this:  
runPrepUpdate generates an error  
runUpdateQuery runs fine, but the same parameters

OneRow = system.db.runPrepUpdate(“insert into aws\_log(tagpath,lasttime) Values(?,?)”, [myTag,lastDate],databaseConnection)  
sqlString = “insert into aws\_log(tagpath,lasttime) Values(’” + myTag + “’,” + str(lastDate) + “)”  
print sqlString  
OneRow = system.db.runUpdateQuery(sqlString, databaseConnection)

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**Author:** ![Sanderd17](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/sanderd17/32/8735_2.png) [@Sanderd17](https://forum.inductiveautomation.com/u/Sanderd17)\
**Post date:** [February 27, 2018, 4:02pm UTC](https://forum.inductiveautomation.com/t/conversion-to-unknown-in-a-query/17155/2 "2018-02-27T16:02:20Z")

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This is a known issue with the JDBC driver for MS SQL shipped with Ignition. That driver can’t handle the conversion from python `long` datatype to SQL `bigint`.

One solution is to pass the parameter as a string `str(...)`, or you can replace the JDBC driver with a newer version.