For example, the range of values for a salary column can be limited by creating a CHECK constraint that allows for only data that ranges from 15,000 through 100,000. Other databases such as PostgreSQL would let you use RegExp using the ~ operator. You can create a CHECK constraint with any logical (Boolean) expression that returns TRUE or FALSE based on the logical operators. You can find more information and instructions at Stack Overflow's How do I use regex in a SQLite query?. However, to be able to use it, you first need to install the sqlite3-pcre pcre regex extension for sqlite3, on a Linux machine (there may be a Windows alternative, but I've not been able to find it). You can actually use a REGEXP operator and write: CHECK (prefix REGEXP '^+$') A uniqueness constraint is an explicit UNIQUE or PRIMARY KEY constraint within the CREATE TABLE statement, or a unique index. The only thing it will complain about are statements like: INSERT INTO test This means your CHECK condition, as originally written, is not actually checking what you expect. In CHECK constraints of a table definition. This prevents application-defined functions from being used in places where an attacker might be able to surreptiously invoke them by modifying a database schema: In VIEWs. Though maybe this is what you want since you. Invoke sqlite3dbconfig(db,SQLITEDBCONFIGTRUSTEDSCHEMA,0,0) on each database connection as soon as it is opened. * in a regexp, and _ meaning (1 of anything), which would be the equivalentof. Also its not anchored with and, so it works on substrings rather than requiring that the whole string match. Actually, you have two metacharacters: % means (0 or more of anything), which would be the equivalent of a. The pattern matches allowed by this operator are very simple, compared to the powerful regexp. The LIKE operator in SQL does not work like regular expressions.
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