Is there any C SQLite API for quoting/escaping the name of a table?

Question

It's impossible to sqlite3_bind_text a table name because sqlite3_prepare_v2 fails to prepare a statement such as:

SELECT * FROM ? ;

I presume the table name is needed to parse the statement, so the quoting needs to happend before sqlite3_prepare_v2.

Is there something like a sqlite3_quote_tablename? Maybe it already exists under a name I can't recognize, but I can't find anything in the functions list.

Answer 1

If a table name has invalid characters in it you can enclose the table name in double quotes, like this.

sqlite> create table "test table" (id);
sqlite> insert into "test table" values (1);
sqlite> select * from "test table";
id
----------
1

Of course you should avoid using invalid characters whenever possible. It complicates development and is almost always unnecessary (IMO the only time it is necessary is when you inherit a project that is already done this way and it's too big to change).

Answer 2

If SQLite doesn't accept table names as parameters, I don't think there is a solution for your problem...

Take into account that:

Parameters that are not assigned values using sqlite3_bind() are treated as NULL.

so in the case of your query, the table name would be NULL which of course is invalid.

Answer 3

When using SQLite prepared statements with parameters the parameter: "specifies a placeholder in the expression for a literal value that is filled in at runtime"

Before executing any SQL statement, SQLite "compiles" the SQL string into a series of opcodes that are executed by an internal Virtual Machine. The table names and column names upon which the SQL statement operates are a necessary part of the compilation process.

You can use parameters to bind "values" to prepared statements like this:

SELECT * FROM FOO WHERE name=?;

And then call sqlite3_bind_text() to bind the string gavinbeatty to the already compiled statement. However, this architecture means that you cannot use parameters like this:

SELECT * FROM ? WHERE name=?;    // Can't bind table name as a parameter
SELECT * FROM FOO WHERE ?=10;    // Can't bind column name as a parameter