• SQL to SequoiaDB shell to C

    SQL to SequoiaDB shell to C

    SequoiaDB 的查询用 json（bson）对象表示，下表以例子的形式显示了 SQL 语句，SequoiaDB shell 语句和 SequoiaDB C 驱动程序语法之间的对照。

    SQLSequoiaDB shellC Driver
    insert into bar( a, b ) values( 1, -1 )db.foo.bar.insert( { a: 1, b: -1 } )const char r = "{ a: 1, b: -1 }" ; jsonToBson ( &obj, r ); sdbInsert( collection, &obj );
    select a,b from bardb.foo.bar.find( null, { a: "", b: "" } )const char r = "{ a: "", b: "" }" ; jsonToBson ( & select, r ) ; sdbQuery ( collection, NULL, &select, NULL, NULL, 0, -1, cursor ) ;
    select from bardb.foo.bar.find()sdbQuery ( collection, NULL, NULL, NULL, NULL, 0, -1, cursor ) ;
    select from bar where age = 20db.foo.bar.find( { age: 20 } )const char r = "{ age: 20 }" ; jsonToBson ( &condition, r ); sdbQuery ( collection, & condition, NULL, NULL, NULL, 0, -1, cursor );
    select from bar where age = 20 order by namedb.foo.bar.find( { age: 20 } ).sort( { name: 1 } )const char r1 = "{ age: 20 }" ; const char r2 = "{ name: 1 }" ; jsonToBson ( & condition, r1 ) ; jsonToBson ( &orderBy, r2 ) ; sdbQuery ( collection, & condition, NULL, & orderBy, NULL, 0, -1, cursor ) ;
    select from bar where age > 20 and age < 30db.foo.bar.find( { age: { $gt: 20, $lt: 30 } } )const char r = "{ age: { $gt: 20, $lt: 30 } }" ; jsonToBson ( &condition, r ); sdbQuery ( collection, & condition , NULL, NULL, NULL, 0, -1, cursor ) ;
    create index testIndex on bar( name )db.foo.bar.createIndex( "testIndex", { name: 1 }, false )const char r = "{ name: 1 }" ; jsonToBson ( &obj, r ); sdbCreateIndex ( collection, &obj, "testIndex", FALSE, FALSE )
    select from bar limit 20 offset 10db.foo.bar.find().limit(20).skip( 10 )sdbQuery ( collection, NULL, NULL, NULL, NULL, 10, 20, cursor ) ;
    select count( ) from bar where age > 20db.foo.bar.find( { age: { $gt: 20 } } ).count()const char r = "{ age: { $gt: 20 } }" ; jsonToBson ( &condition, r ); sdbGetCount ( collection, &condition, &count ) ;
    update bar set a=2 where b=-1db.foo.bar.update( { $set: { a: 2 } }, { b: -1 } )const char r1 = "{ $set: { a: 2 } }" ; const char r2 = "{ b: -1 }" ; jsonToBson ( &rule, r1 ) ; jsonToBson ( &condition, r2 ) ; sdbUpdate( collection, &rule, &condition, NULL ) ;
    delete from bar where a=1db.foo.bar.remove( { a: 1 } )const char *r = "{ a: 1 }" ; jsonToBson ( &condition, r ) ; sdbDelete ( collection, &condition, NULL ) ;