Identifiers
identify anything in a sql statement with a name, for example, table names,
views, procedures, users and so on. Identifiers can be delimited or unlimited.
Delimited identifiers are enclosed in either a single quote ‘ or double quote
“.
Undelimited identifier names
Must start
with a letter or even an underscore. The following table names are legal (Using
the CREATE statement which is covered in more detail later);
CREATE table TAB1 …
CREATE table _TAB1 …
CREATE table _1TAB …
CREATE table TAB1# …
But the following
are not legal table names;
CREATE table 1TAB …
CREATE table @TAB …
CREATE table _TAB@ …
Delimited identifier names
Enclosed in
double quotes “ and can contain any character as well as special characters.
For example, the following are allowed:
CREATE TABLE "TAB1" LIKE _ty_test;
CREATE TABLE "_TAB1" LIKE _ty_test;
CREATE TABLE "_1TAB" LIKE _ty_test;
CREATE TABLE "TAB1#" LIKE _ty_test;
CREATE TABLE "1TAB" LIKE _ty_test;
CREATE TABLE "@TAB" LIKE _ty_test;
CREATE TABLE "_TAB@" LIKE _ty_test;
These statements will create the following objects in
the repository:
By following the rules specified above, the tables
can be deleted using the following syntax. The table name will only be
delimited in instances where it is required:
DROP TABLE TAB1;
DROP TABLE _TAB1;
DROP TABLE _1TAB;
DROP TABLE TAB1#;
DROP TABLE "1TAB";
DROP TABLE "@TAB";
DROP TABLE "_TAB@";
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