Byte Type Is Returned After a Table Column of the Character Type Is Read in Java

Symptom

A column in a newly created database table is of the character type. However, after the column is read in Java, the returned type is byte.

For example, to create a sample table table01, run the following command:

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CREATE TABLE IF NOT EXISTS table01(
   msg_id character(36),
   msg character varying(50)
);

In Java, the code for reading the field of the character type is as follows:

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ColumnMetaInfo(msg_id,1,Byte,true,false,1,true);

Possible Causes

• CHARACTER(n) is a fixed-length character string. When the actual string length is insufficient, the database pads it with spaces. Then, Java uses the byte type to receive the string.
• CHARACTER VARYING(n) is a variable-length character string. Java uses the string type to receive it.