Sqlite – How to check in SQLite whether a table exists

sqlite

How do I, reliably, check in SQLite, whether a particular user table exists?

I am not asking for unreliable ways like checking if a "select *" on the table returned an error or not (is this even a good idea?).

The reason is like this:

In my program, I need to create and then populate some tables if they do not exist already.

If they do already exist, I need to update some tables.

Should I take some other path instead to signal that the tables in question have already been created – say for example, by creating/putting/setting a certain flag in my program initialization/settings file on disk or something?

Or does my approach make sense?

Best Answer

I missed that FAQ entry.

Anyway, for future reference, the complete query is:

SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';

Where {table_name} is the name of the table to check.

Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database Schema

This will return a list of tables with the name specified; that is, the cursor will have a count of 0 (does not exist) or a count of 1 (does exist)

Related Solutions

Sql – How to list the tables in a SQLite database file that was opened with ATTACH

There are a few steps to see the tables in an SQLite database:

List the tables in your database:
```
.tables
```
List how the table looks:
```
.schema tablename
```
Print the entire table:
```
SELECT * FROM tablename;
```
List all of the available SQLite prompt commands:
```
.help
```

Sqlite primary key on multiple columns

According to the documentation, it's

CREATE TABLE something (
  column1, 
  column2, 
  column3, 
  PRIMARY KEY (column1, column2)
);

Best Answer

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Sql – How to list the tables in a SQLite database file that was opened with ATTACH

Sqlite primary key on multiple columns

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