The best replacement for oracle spatial is locator.

The best alternatives to oracle spatial are rated as following:
★★★★★  locator
★★★★  esri
★★★  sql server spatial
★★  postgis
★  arcsde

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Speaking about oracle spatial, one probably shouldn't forget about arcsde.

Other search terms related to oracle spatial and their ratings are:
★★★★★ arcsde
★★★★ geoserver
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oracle spatial
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