How to Efficiently Retrieve a List of Column Names from an SQLite3 Table?

Accessing SQLite3 Table Column Names Efficiently

When upgrading an iOS app's database, verifying the presence of specific columns is crucial. While a SELECT statement can be used, it requires parsing the output to extract column names. A more efficient and common method leverages the PRAGMA table_info() command.

The PRAGMA table_info() Method

This command directly lists all columns within a given table. The syntax is simple:

PRAGMA table_info(table_name);

The result is a table, with each row representing a column. The name column holds the column's name.

Example: Retrieving users Table Columns

To obtain the column names from a table named users, use:

PRAGMA table_info(users);

This yields a result set similar to:

cid	name	type	notnull	dflt_value	pk
0	id	INTEGER	1	NULL	1
1	name	TEXT	0	NULL	0
2	age	INTEGER	0	NULL	0
3	email	TEXT	0	NULL	0

The PRAGMA table_info() approach is superior for its directness and efficiency in retrieving SQLite3 column names.

The above is the detailed content of How to Efficiently Retrieve a List of Column Names from an SQLite3 Table?. For more information, please follow other related articles on the PHP Chinese website!