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Problems with update function from Matlab to MySQL

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Beatrice Sonzogni
Beatrice Sonzogni on 6 Jul 2021
Answered: Kojiro Saito on 8 Jul 2021
Hi, I'm dealing with a problem with the update function in Matlab.
conn=database('MySQL','user','password');)
selectquery_select = 'SELECT * FROM inputs WHERE i_read = 0';
data_select = select(conn,selectquery_select);
for j=1:size(data_select)
id_data = data_select(j,1);
id_data = string(id_data.(1));
time_data = data_select(j,4);
time_data = string(time_data.(1));
time_dataform = datetime(time_data,'InputFormat','yyyy-MM-dd HH:mm:ss');
y0=data_select(j,2);
y0 = str2num(string(y0.(1)));
r0=data_select(j,3);
r0 = str2num(string(r0.(1)));
if id_data == "115"
run("C:\Users\...\uu.m")
update(conn,'inputs','i_read',1,'WHERE (ID_code = "115") AND WHERE (i_Time = time_data)');
end
end
Basically, I'm taking some value from the database when i_read is equal to 0 (i_read is a boolean variable in the database that should give 1 if the value is already processed and 0 if not). After a value is read, we want to change the i_read in the database from 0 to 1. We decide to use the update function, but this gave us the following error:
Error using database.odbc.connection/update
Too many input arguments.
Error in Patient_Identification (line 57)
update(conn,'inputs','i_read',1,'WHERE (ID_code = "112") AND WHERE (i_Time = ', time_data,')');
Someone is able to help us with this problem? Thank you.

Answers (1)

Kojiro Saito
Kojiro Saito on 8 Jul 2021
Multiple whereclause does not need WHERE more than once.
So, the following would work. Changed from AND WHERE to AND.
update(conn,'inputs','i_read',1,'WHERE (ID_code = "115") AND (i_Time = time_data)');
If ID_code column is defined as INTEGER not CHAR nor VARCHAR, you don't need to use double quotation.
update(conn,'inputs','i_read',1,'WHERE (ID_code = 115) AND (i_Time = time_data)');
Please try both.

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