How do I check if a table exists in sqlite3 c++ API? [duplicate]

This question already has answers here: How do I check in SQLite whether a table exists? 开发者_如何学C (29 answers) Closed 3 years ago.

I'm opening a database file and potentially creating it if it doesn't exist.

But for some reason, this doesn't create the table. Any ideas?

const char* sql = "CREATE TABLE IF NOT EXISTS blocks(id text primary_key,length numeric)";

sqlite3_stmt *stmt;
rc = sqlite3_prepare_v2(db_, create_table_sql, -1, &stmt, NULL);
rc = sqlite3_step(stmt);

I haven't got it in here by yes I'm checking the return code at each point. There are no errors.

Perhaps there is a better way to accomplish this?

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Variation on another given answer:

select count(type) from sqlite_master where type='table' and name='TABLE_NAME_TO_CHECK';

Will return 0 if table does not exist, 1 if it does.

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Execute the following SQL:

select 1 from sqlite_master where type='table' and name='TABLE_NAME_TO_CHECK'

If you get a row then the table exists. If the result set is empty then it doesn't.

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It looks like you're missing a right parenthesis in the SQL. It should be:

const char* sql = "CREATE TABLE IF NOT EXISTS blocks(id text primary_key,length numeric);";