sql: support specifying custom index parameters for geospatial indexes

[otan]

Release note (sql change): Introduced the s2_max_level, s2_level_mod
and s2_max_cells storage parameters for modifying the S2 parameters
for indexing GEOMETRY and GEOGRAPHY data types in an inverted index.

Release note (sql change): Introduced the geometry_min_x,
geometry_min_y, geometry_max_x, geometry_max_y storage parameters
for indexing GEOMETRY data types in an inverted index.

[cockroach-teamcity]

This change is 

[sumeerbhola]

Thanks for doing this!

Reviewed 10 of 10 files at r1.
Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @otan)

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pkg/sql/create_index.go, line 116 at r1 (raw file):

		return a.applyS2ConfigSetting(evalCtx, key, expr, 0, 30)
	case `s2_level_mod`:
		return a.applyS2ConfigSetting(evalCtx, key, expr, 1, 30)

s2.RegionCoverer only supports LevelMod from 1...3.

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pkg/sql/schemaexpr/partial_index.go, line 174 at r1 (raw file):

		if index.GeoConfig.S2Geometry != nil {
			if len(index.ColumnIDs) != 1 {

why should there be only 1 columnID? The first columnID is the inverted column, but there are also the PK columns.

[otan]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @sumeerbhola)

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pkg/sql/create_index.go, line 116 at r1 (raw file):

Previously, sumeerbhola wrote…

s2.RegionCoverer only supports LevelMod from 1...3.

Fixed.

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pkg/sql/schemaexpr/partial_index.go, line 174 at r1 (raw file):

Previously, sumeerbhola wrote…

why should there be only 1 columnID? The first columnID is the inverted column, but there are also the PK columns.

I think this is the way it is stored on the descriptor -- in which case this is the only column.

[sumeerbhola]

Reviewed 2 of 2 files at r2.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @sumeerbhola)

[otan]

bors r=sumeerbhola

[craig]

Build succeeded:

• Compile Build (Cockroach)