Sometimes you just want to see the basic structure of a table.
In SQLite, there are several ways to retrieve information about a given table. In particular, here are four options:
PRAGMA table_info() statementPRAGMA table_xinfo() statement (for virtual tables).schema commandsqlite_master tableExamples of each method are below.
In PostgreSQL you can use the extract() function to get the year from a date.
You can also use the date_part() function to do the same thing.
When it comes to backing up your databases in SQLite, you have a few options as to how to go about it.
In particular, you can use one of the following methods:
.backup command to back up a specified database.dump command to export the database to a .sql file.clone command to clone the databaseSQLite doesn’t have a concat() function like many other database management systems, such as SQL Server’s concat() and MySQL’s concat().
However, that doesn’t mean you can’t concatenate two strings in SQLite.
SQLite has a concatenation operator (||) that you can use to concatenate two strings.
In SQLite, you can use the instr() function to return the position of a given character within a string.
The function only returns the position of the first occurrence of the character (if any).
If the character isn’t found, then it returns 0.
If either of the arguments are NULL, then it returns NULL.
The SQLite quote() function allows you to escape a string so that it’s suitable for inclusion in an SQL statement.
Strings are surrounded by single-quotes with escapes on interior quotes.
BLOBs are encoded as hexadecimal literals.
Note that strings with embedded NUL characters cannot be represented as string literals in SQL. If you include strings with embedded NUL characters, the returned string literal is truncated prior to the first NUL.