java - is it worth to learn google data store -

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i want use google app hosting , have read don't give option of mysql or sql.

now building java website using mysql.

is data store same sql. , work hibernate

should learn or not

the datastore not "drop in" replacement sql. have worked python version of gae bit, java version might different...

  • you want limit number of queries run in page , number of objects query. doing otherwise lead looooong load times. inserting lots of data (200+ objects) wont work.

  • you can't range scans on more 1 column in table (for instance 1 < x < 2 , 3 < y < 4). lot of query types not supported compared full fledged database engine.

  • you should edit , insert data via program. datastore admin allows insert data after initial object created types (text,blob) not editable.

  • any changes models require loop through instances , make changes (especially if delete attribute on model). can ignore chances want reclaim space used.

  • backing data , uploading data application bit more complicated. remote api makes things easier compared of tools other engines seems primitive.


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