I actually faced an issue about null values in MySQL workbench, Null values are automatically replaced by other random values... how is it so??
Here is the image of table in workbench:
Here is the image from the excel containing null values:
Related
Using Dbeaver, I am trying to add a new column using an existing column to update it. However, after an update to the new column, other column values are changed (to NULL). I am unsure what is the issue?
Before the update:
My statements:
ALTER TABLE project1.nhd
ADD "Address" varchar;
UPDATE project1.nhd
SET "Address" = SPLIT_PART("PropertyAddress", ',', 1);
After the update:
I thought the issue was the method of data transfer, so I tried importing the CSV as a database in Dbeaver and then exporting it to the table and using COPY to import the data into the table. However, the result was the same.
I have a two column csv file that has only numeric data. I create a table in Postgre with the columns as numeric. I successfully use the import wizard, but it gives all my values in the postgre table as null. Not sure why.
Using pgadmin, I am trying to import data into a table from a CSV file - as it's a lot faster than running SQL scripts.
I am having problem when one of the column value is 'NULL'. The problem is that postgres is taking it as null where as this should really be 'NULL'. How can I avoid this?
in other words, the below CSV import fails:
my_column
A1B2
NULL // Postgres fails here because it thinks I am inserting a null into non-nullable column, but it's a text value
Thanks,
I have a TSV file that I want to load into redshift via the copy command.
I want one of the fields in the table to be a timestamp that registers the time the row was loaded.
I have defined a field like this:
ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP
This works fine if I insert into this row at the psql command line, without specifying a value for this column - it defaults to the current timestamp as expected.
However, what can I have in my TSV file in that column that will cause redshift to default to the current timestamp?
If I use \N in my TSV, then I just get a NULL in the ts field.
On the other hand, if I define my column as NOT NULL
ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL
then I get an error from the COPY command that I can't insert NULL values into a NOT NULL field.
On mysql, mysql would convert a NULL value into the current timestamp, but redshift's behaviour is to throw an error.
Any suggestions? Many thanks!
I've been banging my head over this for a while and found one partial workaround: you can have ts column as the last column of your table and the TSV file with all the other columns but this one. The file will be read with the columns that exist and loaded into the consecutive list of columns with the same width in the target table, leaving all columns beyond that width with default values, i.e. you can have id | ts table and load the file with id only and ts will take the default. The current timestamp column is typically a metadata column, so it's ok to place it at the end of the table.
I am using PostgreSQL 9.6. I have created a table with create query.
But when i checked in left panel of pgAdmin, under table i found more six columns named tableid,cmax,xmax,cmin,xmin and ctid.
When i searched about this, I found that these are OIDs column and does not affect to data on other columns.
I have to import data into this table. So after selecting table, from right click i got option for import/Export. So from that i am importing .csv file.
But when i tried to import the data in table, i am getting error like,
ERROR: column "tableoid" of relation "account" does not exist
Please suggest me how to eliminate these OID columns from table.
You must be missing some column that is present in the csv named "tableoid".
In this case ,TABLE according to the import file must be created first. IF there is no prior table , it wont work. This may help.
http://www.postgresqltutorial.com/import-csv-file-into-posgresql-table/