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I screwed up and created a column as a varchar(255) where that is no longer sufficient. I've read that varchar has no performance benefits over text on Postgres, and so would like to convert the varchar to a text column in a safe way that preserves the data.
What's the best way for me to do this?
577
Both TEXT and VARCHAR have the upper limit at 1 Gb, and there is no performance difference among them (according to the PostgreSQL documentation).
Some Differences Between VARCHAR and TEXT While both data types share a maximum length of 65,535 characters, there are still a few differences: The VAR in VARCHAR means that you can set the max size to anything between 1 and 65,535. TEXT fields have a fixed max size of 65,535 characters.
First, specify the name of the table to which the column you want to change belongs in the ALTER TABLE clause. Second, give the name of column whose data type will be changed in the ALTER COLUMN clause. Third, provide the new data type for the column after the TYPE keyword.
A cast specifies how to perform a conversion between two data types. For example, SELECT CAST(42 AS float8); converts the integer constant 42 to type float8 by invoking a previously specified function, in this case float8(int4) . (If no suitable cast has been defined, the conversion fails.)
ALTER TABLE table1 ALTER COLUMN column1 TYPE text; If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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