The browser based WebSQL specification was an in browser database and has been supported by Chrome and a number of other browsers for some time. However, the specification has been dropped in favour of IndexedDB and chrome will be dropping support for it in a future version. As you have invested some time into developing a WebSQL system this isn’t great news as it is unlikely that IE will implement it in the future.
Ido Green a developer Advocate at Google Chrome has written a nice post this week showing you how to convert a WebSQL database into an IndexedDB one which you can find here.
IndexedDb and WebSQL are fundamentally different types of database below is a table that tries to explain some of the differences in the concepts between the two approaches:
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Concept
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Relational DB
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IndexedDB
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Database
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Database
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Database
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Tables
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Tables contain columns and rows
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objectStore contains Javascript objects and keys
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Query Mechanism, Join, and Filters
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SQL
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Cursor APIs, Key Range APIs, and Application Code
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Transaction Types and Locks
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Lock can happen on databases, tables,
or rows on READ_WRITE Transactions
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Lock can happen on database on VERSION_CHANGE transaction, on an objectStores on READ_ONLY and READ_WRITE transactions. There is no object level locking.
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Transaction Commits
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Transaction creation is explicit. Default is to rollback unless I call commit.
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Transaction creation is explicit. Default is to commit unless I call abort or there is an exception that is not caught.
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Property Lookups
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SQL
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Indexes are required to query object properties directly
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Records/Data
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Normal form and single valued properties
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De-normal form and can have multi-valued properties
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