Queries and data

A query is a table of rows and named columns. You can build one in memory or obtain one from a database.

Database functions are available in native builds with datasource support, not in the browser playground.

In-memory queries

people = queryNew(
    "id,name",
    "integer,varchar",
    [ [ 1, "Ann" ], [ 2, "Bob" ] ]
);

println( people.recordCount );
println( people.name[ 2 ] );

for ( person in people ) {
    println( person.id & ":" & person.name );
}

2
Bob
1:Ann
2:Bob

Functions such as queryAddRow, queryGetCell, querySetCell and queryColumnData let you work with rows and columns directly. Query indexes start at 1.

Datasources

Register a datasource, then pass its name to queryExecute. MatchBox provides SQLite and PostgreSQL drivers.

datasourceRegister( "main", {
    driver: "sqlite",
    database: "app.db"
} );

people = queryExecute(
    "select id, name from people where id = ?",
    [ 1 ],
    { datasource: "main" }
);

The example assumes the database has a people table. Use query parameters rather than joining user input into SQL. Datasources can also be declared in matchbox.toml.

Transactions and query of queries

Use transactionBegin, transactionCommit and transactionRollback to group database changes.

Query of queries runs SQL over in-memory query data using dbtype: "query"; it requires a build with the qoq feature. See source builds for custom runtime features and the query function reference for available functions.