Maximum Index Width

Help Query Tuning
1

Hi Memsql Community,
I can read in the docs the maximum columns in an index is 32,
But what is the maximum size in KB/ Width of the indexed columns?

in many other RDBMS:
mysql - 767 bytes of a single column (can be increased with some special config)
mssql - 900 bytes for a clustered index. 1,700 for a nonclustered index. for memory-optimized tables 2500 bytes for a nonclustered index

so whats the total & single column size that will be indexed.

example: would 3 TEXT columns (65,535 bytes) would be fully indexed.

Thanks!

2

MemSQL doesn’t have any limitations on the sizes of the columns you create indexes on. MemSQL doesn’t copy the indexed columns used in seconday keys. The keys refer to the primary key row.

Their is a maximum row-size of 64K for on-row data though. MemSQL stores any variable sized columns (VARCHAR, VARBINARY) off-row so these only count for 8 bytes of on-row data. Unless you have a lot of decimal columns or CHAR columns your not likely to ecounter this limit.

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