SQLite Prepared Statement for Create Table error - sqlite

I'm running into an error trying to use a SQLite prepared statement:
create table RawRecord (?, ?, ?);
Calling sqlite3_prepare16_v2 gives me this error: SQLITE_ERROR: SQLITE_ERROR[1]: near "?": syntax error
I don't run into problems with prepared statements anywhere else (and have been using SQLite for many years). I have tried to find whether prepared statements are simply not allowed for CREATE TABLE, but haven't found anyone saying that's the case.
If I build the create string manually and embed my column names, it works. I prefer to use prepared statements simply because it makes things like quotes cleaner, and in this case the column names come from user data, so I don't know what they will be.
I can certainly work around this, but was hoping to understand why this is an error.
Help?

Related

How to implement INSERT where not exists for ORACLE in Mule4

I am trying to implement a use-case in Mule4 where a tour needs to be assigned to a user if it has not already been assigned.
I was hoping that I could implement it using Mule db:insert component and using INSERT WHERE NOT EXISTS SQL script as below.
INSERT INTO TL_MAPPING_TOUR(TOURNO,TLID,SYSTEM) select :tourno,:tlid,:system from DUAL
where not exists(select * from TL_MAPPING_TOUR where (TOURNO=:tourno and TLID=:tlid and SYSTEM=:system))
However, this is resulting in Mule Exception
Message : ORA-01722: invalid number
Error type : DB:BAD_SQL_SYNTAX
TL_MAPPING_TOUR table has an id column (Primary Key), but that is auto-generated by a sequence.
The same script, modified for running directly in SQL developer, as shown below, is working fine.
INSERT into TL_MAPPING_TOUR(TOURNO,TLID,SYSTEM)
select 'CLLO001474','123456789','AS400'
from DUAL
where not exists(select * from TL_MAPPING_TOUR where (TOURNO='CLLO001474' and TLID='123456789' and SYSTEM='AS400'));
Clearly Mule db:insert component doesn't like the syntax, but it's not very clear to me what is wrong here. I can't find any INSERT WHERE NOT EXISTS example implementation for the Mule4 Database component either.
stackoverflow page https://stackoverflow.com/questions/54910330/insert-record-into-sql-server-when-it-does-not-already-exist-using-mule directs to page not found.
Any idea what is wrong here and how to implement this in Mule4 without using another Mule4 db:select component before db:insert?
I don't know "mule4", but this:
Message : ORA-01722: invalid number
doesn't mean that syntax is wrong (as you already tested it - the same statement works OK in another tool).
Cause: You executed a SQL statement that tried to convert a string to a number, but it was unsuccessful.
Resolution:
The option(s) to resolve this Oracle error are:
Option #1: Only numeric fields or character fields that contain numeric values can be used in arithmetic operations. Make sure that all expressions evaluate to numbers.
Option #2: If you are adding or subtracting from dates, make sure that you added/substracted a numeric value from the date.
In other words, it seems that one of columns is declared as NUMBER, while you passed something that is a string. Oracle performed implicit conversion when you tested the statement in SQL Developer, but it seems that mule4 didn't and hence the error.
The most obvious cause (based on what you posted) is putting '123456789' into TLID as other values are obviously strings. Therefore, pass 123456789 (a number, no single quotes around it) and see what happens. Should work.
SQL Developer is too forgiving. It will convert string to numbers and vise versa automatically when it can. And it can a lot.
Mulesoft DB connector tries the same but it is not as succefule as native tools. Pretty often it fails to convert, especially on dates but this is not your case.
In short - do not trust too much data sense of Mulesoft. If it works - great! Otherwise try to eliminate any intelligence from it and do all conversions in the query and better from the string. Usually number works fine but if doesn't - use to_number function to mark properly that this is the number.
More about this is here https://simpleflatservice.com/mule4/AvoidCoversionsOrMakeThemNative.html

SQLite report on conflict

I'm using INSERT OR IGNORE and INSERT OR REPLACE , I'm trying to get SQLite to report whenever the OR IGNORE or OR REPLACE condition occurred.
I looked into using TRIGGER but wasn't able to get it to work as expected.
The desired behaviour is to raise a warning when the OR condition was true.
It would be possible to combine AFTER INSERT/DELETE triggers with user-defined functions to report whether some rows got inserted/deleted or not.
However, these statements are intended to be used when you do not care about which case actually happened.
The easiest way to detect if the same value already exists in the table is to run a SELECT.

RowCount,Table must Exist, Delete All Rows from Table keywords from Robotframework

I am new to robotframework and I am trying to get the hang of the keywords of DatabaseLibrary. I am getting error at 3 of such keywords.
1) I am using rowcount keywords as below-
${rowCount} Row Count <sql query>
And I always get ${rowCount}=0 irrespective of the number of rows in my table.
2) I am using Delete All Rows From Table as below-
Delete All Rows From Table <Table_Name>
And I get ORA-00911: invalid character but if use the same table with other keywords like Query ,it works fine.
3) I am using Table Must Exist as below-
Table Must Exist <Table_Name>
And I get ORA-00942: table or view does not exist but this table is very much there.
Please help me find what am I doing wrong.
Thanks in Advance!!!
I could be wrong but I believe a colleague told me there were issues, at the very least with the Row Count keyword.
However, for all three options there are easy solutions, which you've even hinted at in your question by using Query or Execute SQL Script
1)
${result}= Query Select count(id) from table
${rc} = ${result[0][0]} #Play with this as I forget exact syntax
2) Put your delete script in a test scripts folder with your tests and call it using Execute SQL script. You could also use Query to perform a select query before and after to confirm expected states.
3) Again perform a query against the table you're expecting to be there, a simple row count on id would do for this purpose. You could set a variable based on the result and use this again later if required.
I had similar issues.
I use cx_Oracle.
With the Table Must Exist keyword my problem was the same.
I dont really understand why, but first I have to use Encode String to Bytes keyword.
And I need to use a DatabaseLibrary 0.8 at least, because earlier versions didnt have solution for cx_Oracle. These solved this issue for me.
But with Delete all rows from table I still have problems.
Because this keyword puts a ; at the end of the line and it passes on that line to execute query if I understand weel, so it still causes an ORA-00911 error for me.
With Execute Sql String and the command DELETE FROM tablename you can have the same results, but it will work this way.
I hope it helps a little

UPDATE statement not working in sqlite

I'm using the following command to update a field in my database:
UPDATE Movies SET 'From'=2 WHERE 'Name'="foo";
I'm using sqlite3.exe in windows (command prompt). Although no error message is produced, nothing changes in the table. I examined the database with a couple of gui tools and I'm sure UPDATE does nothing.
'From' is of type integer and 'Name' is text.
The problem you've got is that you're getting your quoting wrong. SQLite follows the SQL standard here, and that specifies what quote characters to use: '…' is for strings, and "…" is for tokens (like special names used as column or table names). Sometimes it manages to guess what you mean anyway and compensate for getting it wrong, but it can't with the WHERE clause because that is syntactically correct (if decidedly unhelpful):
Swapping the quoting appears to work:
UPDATE Movies SET "From"=2 WHERE "Name"='foo';
Those aren't good column names. Both are keywords, best avoided, and not self-explanatory at all.
Do a SELECT to see how many rows match the WHERE clause in the UPDATE. If none come back, you have your answer.
Did you commit the UPDATE? Is auto commit turned on?

Verifying sqlite FTS (Full Text Search) syntax, and how to do a single term NOT search

Is there a way to determine if a MATCH query sent to an fts3 table in sqlite is valid? Currently, I don't find out if the expression is invalid until I try to run it, which makes it a little tricky. I'd like to report to the user that the syntax is invalid before even trying to run it.
I'm using sqlite with the C api.
Additionally, doing a search with the expression "NOT " will fail with a "SQLlite logic/database error". Googling seems to indicate that such a query is invalid. Is there a correct syntax to do the operation? I'm essentially trying to find entries that do NOT contain that term. Or do I have to drop back down to using LIKE and do a sequential scan and not use FTS?
Looks like the simplest way right now is to create a separate FTS table with no rows, and execute the query against it. It will be immediate since there's no data in the table, and will report and error if the query syntax is incorrect.

Resources