Using PRAGMAs as sources in SQLite in getting colu

问题:

Problem:

I want to do this operation

select name from pragma table_info(my_awesome_table)

However, it yields a syntax error. I have the sneaking suspicion this is possible, but it doesn't seem to be documented as usable in the SELECT docs with sqlite.

回答1:

Pragmas are SQLite-specific extension to SQL, it has a special syntax:

sqlite> create table my_table (a int, b TEXT);
sqlite> .headers ON
sqlite> .mode columns
sqlite> pragma table_info(my_table);
cid         name        type        notnull     dflt_value  pk
----------  ----------  ----------  ----------  ----------  ----------
0           a           int         0                       0
1           b           TEXT        0                       0

You can not specify columns, and you can not use pragmas in a subquery.