"value too long for type character varying" Is Displayed When VARCHAR(n) Stores Chinese Characters

Symptom

The VARCHAR(18) field cannot store eight Chinese characters. The following error is reported:

1

org.postgresql.util.PSQLException: ERROR: value too long for type character varying(18)

Possible Causes

Take UTF-8 encoding as an example. A Chinese character is 3 to 4 bytes long. Eight Chinese characters are 24 to 32 bytes long, which exceeds the maximum length (18 bytes) of VARCHAR(18).

If a column contains Chinese characters, you can use the char_length or length function to query the character length and use the lengthb function to query the byte length.

Handling Procedure

varchar(n) is used to store variable length value as a string, here n denotes the string length in bytes. A Chinese character is usually 3 to 4 bytes long.

Increase the value length of this field based on the actual Chinese character length. For example, to store eight Chinese characters in a field, n must be set to at least 32, that is, varchar(32).