CREATE TABLE 문 또는 ALTER TABLE 문을 사용하여 BLOB/CLOB 타입 컬럼을 생성/추가/삭제할 수 있다.
-- creating a table and CLOB column
CREATE TABLE doc_t (doc_id VARCHAR(64) PRIMARY KEY, content CLOB);
-- an error occurs when UNIQUE constraint is defined on CLOB column
ALTER TABLE doc_t ADD CONSTRAINT content_unique UNIQUE(content);
-- an error occurs when creating an index on CLOB column
CREATE INDEX ON doc_t (content);
-- creating a table and BLOB column
CREATE TABLE image_t (image_id VARCHAR(36) PRIMARY KEY, doc_id VARCHAR(64) NOT NULL, image BLOB);
-- an error occurs when adding a BOLB column with NOT NULL constraint
ALTER TABLE image_t ADD COLUMN thumbnail BLOB NOT NULL;
-- an error occurs when adding a BLOB column with DEFAULT attribute
ALTER TABLE image_t ADD COLUMN thumbnail2 BLOB DEFAULT BIT_TO_BLOB(X'010101');