asc_tolower asc_toupper datum_lower datum_textcat datum_upper pg_lower pg_upper pnstrdup text_catenate textfunc_ttext textfunc_ttext_text textfunc_ttext_ttext

pg_upper() Datum pg_upper ( text *  txt ) Convert the text value to uppercase. Note Function adapted from the external function upper() in varlena.c. Notice that DEFAULT_COLLATION_OID is used instead of PG_GET_COLLATION().