ExplainTest

ExplainTest is a explain test command tool, also with some useful test cases for TiDB execute plan logic, we can run case via run-tests.sh.

Usage: ./run-tests.sh [options]

    -h: Print this help message.

    -s <tidb-server-path>: Use tidb-server in <tidb-server-path> for testing.
                           eg. "./run-tests.sh -s ./explaintest_tidb-server"

    -b <y|Y|n|N>: "y" or "Y" for building test binaries [default "y" if this option is not specified].
                  "n" or "N" for not to build.
                  The building of tidb-server will be skiped if "-s <tidb-server-path>" is provided.

    -r <test-name>|all: Run tests in file "t/<test-name>.test" and record result to file "r/<test-name>.result".
                        "all" for running all tests and record their results.

    -t <test-name>: Run tests in file "t/<test-name>.test".
                    This option will be ignored if "-r <test-name>" is provided.
                    Run all tests if this option is not provided.

    -v <vendor-path>: Add <vendor-path> to $GOPATH.

    -c <test-name>|all: Create data according to creating statements in file "t/<test-name>.test" and save stats in "s/<test-name>_tableName.json".
                    <test-name> must has a suffix of '_stats'.
                    "all" for creating stats of all tests.

    -i <importer-path>: Use importer in <importer-path> for creating data.

    -p <portgenerator-path>: Use port generator in <portgenerator-path> for generating port numbers.

How it works

ExplainTest will read test case in t/*.test, and execute them in TiDB server with s/*.json stat, and compare explain result in r/*.result.

For convenience, we can generate new *.result and *.json from execute by use -r parameter for run-tests.sh

Usage

Regression Execute Plan Modification

After modify code and before commit, please run this command under TiDB root folder.

make dev

or

make explaintest

It will identify execute plan change.

Generate New Stats and Result from Execute

First, add new test query in t/ folder.

cd cmd/explaintest
./run-tests.sh -r [casename]
./run-tests.sh -c [casename]
``
It will generate result and stats base on last execution, and then we can reuse them or open editor to do some modify.