MySQL blob: how to get just a subset of the stored data -


i use mysql storage system huge number of files. read/write portion of data stored in column (data stored bytes) don't have load entire file application (because can > gb). so, in brief, have random read/write access in blob column without loading entire data memory. there functions available perform these operations? thank you.

mysql treats blobs same strings (more or less):

blob values treated binary strings (byte strings). have no character set, , sorting , comparison based on numeric values of bytes in column values.

so usual string functions work on blobs. in particular, can use substring grab part of of blob.

that said, storing multi-gigabyte data file in relational database blob isn't best thing do. you'd better off storing file's metadata in database , leaving file in file system; file systems pretty @ managing files, relational databases @ handling structured data.


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