The join is done on columns or indexes. If joining columns oncolumns, the DataFrame indexes will be ignored. Otherwise if joining indexeson indexes or indexes on a column or columns, the index will be passed on.When performing a cross merge, no column specifications to merge on areallowed.
Incorporates changes from the named commits (since the time theirhistories diverged from the current branch) into the currentbranch. This command is used by git pull to incorporate changesfrom another repository and can be used by hand to merge changesfrom one branch into another.
Then "git merge topic" will replay the changes made on thetopic branch since it diverged from master (i.e., E) untilits current commit (C) on top of master, and record the resultin a new commit along with the names of the two parent commits anda log message from the user describing the changes. Before the operation,ORIG_HEAD is set to the tip of the current branch (C).
The second syntax ("git merge --abort") can only be run after themerge has resulted in conflicts. git merge --abort will abort themerge process and try to reconstruct the pre-merge state. However,if there were uncommitted changes when the merge started (andespecially if those changes were further modified after the mergewas started), git merge --abort will in some cases be unable toreconstruct the original (pre-merge) changes. Therefore:
Note that fast-forward updates do not create a merge commit andtherefore there is no way to stop those merges with --no-commit.Thus, if you want to ensure your branch is not changed or updatedby the merge command, use --no-ff with --no-commit.
Invoke an editor before committing successful mechanical merge tofurther edit the auto-generated merge message, so that the usercan explain and justify the merge. The --no-edit option can beused to accept the auto-generated message (this is generallydiscouraged).The --edit (or -e) option is still useful if you aregiving a draft message with the -m option from the command lineand want to edit it in the editor.
Older scripts may depend on the historical behaviour of not allowing theuser to edit the merge log message. They will see an editor opened whenthey run git merge. To make it easier to adjust such scripts to theupdated behaviour, the environment variable GIT_MERGE_AUTOEDIT can beset to no at the beginning of them.
This option determines how the merge message will be cleaned up beforecommitting. See git-commit for more details. In addition, ifthe is given a value of scissors, scissors will be appendedto MERGE_MSG before being passed on to the commit machinery in thecase of a merge conflict.
Specifies how a merge is handled when the merged-in history isalready a descendant of the current history. --ff is thedefault unless merging an annotated (and possibly signed) tagthat is not stored in its natural place in the refs/tags/hierarchy, in which case --no-ff is assumed.
With --ff, when possible resolve the merge as a fast-forward (onlyupdate the branch pointer to match the merged branch; do not create amerge commit). When not possible (when the merged-in history is not adescendant of the current history), create a merge commit.
GPG-sign the resulting merge commit. The keyid argument isoptional and defaults to the committer identity; if specified,it must be stuck to the option without a space. --no-gpg-signis useful to countermand both commit.gpgSign configuration variable,and earlier --gpg-sign.
Produce the working tree and index state as if a real mergehappened (except for the merge information), but do not actuallymake a commit, move the HEAD, or record $GIT_DIR/MERGE_HEAD(to cause the next git commit command to create a mergecommit). This allows you to create a single commit on top ofthe current branch whose effect is the same as merging anotherbranch (or more in case of an octopus).
Use the given merge strategy; can be supplied more thanonce to specify them in the order they should be tried.If there is no -s option, a built-in list of strategiesis used instead (ort when merging a single head,octopus otherwise).
Verify that the tip commit of the side branch being merged issigned with a valid key, i.e. a key that has a valid uid: in thedefault trust model, this means the signing key has been signed bya trusted key. If the tip commit of the side branch is not signedwith a valid key, the merge is aborted.
Automatically create a temporary stash entry before the operationbegins, record it in the special ref MERGE_AUTOSTASHand apply it after the operation ends. This meansthat you can run the operation on a dirty worktree. However, usewith care: the final stash application after a successfulmerge might result in non-trivial conflicts.
By default, git merge command refuses to merge historiesthat do not share a common ancestor. This option can beused to override this safety when merging histories of twoprojects that started their lives independently. As that isa very rare occasion, no configuration variable to enablethis by default exists and will not be added.
After the rerere mechanism reuses a recorded resolution onthe current conflict to update the files in the workingtree, allow it to also update the index with the result ofresolution. --no-rerere-autoupdate is a good way todouble-check what rerere did and catch potentialmismerges, before committing the result to the index with aseparate git add.
If there were uncommitted worktree changes present when the mergestarted, git merge --abort will in some cases be unable toreconstruct these changes. It is therefore recommended to alwayscommit or stash your changes before running git merge.
git merge --abort is equivalent to git reset --merge whenMERGE_HEAD is present unless MERGE_AUTOSTASH is also present inwhich case git merge --abort applies the stash entry to the worktreewhereas git reset --merge will save the stashed changes in the stashlist.
Before applying outside changes, you should get your own work ingood shape and committed locally, so it will not be clobbered ifthere are conflicts. See also git-stash.git pull and git merge will stop without doing anything whenlocal uncommitted changes overlap with files that git pull/gitmerge may need to update.
To avoid recording unrelated changes in the merge commit,git pull and git merge will also abort if there are any changesregistered in the index relative to the HEAD commit. (Specialnarrow exceptions to this rule may exist depending on which mergestrategy is in use, but generally, the index must match HEAD.)
Often the current branch head is an ancestor of the named commit.This is the most common case especially when invoked from gitpull: you are tracking an upstream repository, you have committedno local changes, and now you want to update to a newer upstreamrevision. In this case, a new commit is not needed to store thecombined history; instead, the HEAD (along with the index) isupdated to point at the named commit, without creating an extramerge commit.
A merged version reconciling the changes from all branches to bemerged is committed, and your HEAD, index, and working tree areupdated to it. It is possible to have modifications in the workingtree as long as they do not overlap; the update will preserve them.
For conflicting paths, the index file records up to threeversions: stage 1 stores the version from the common ancestor,stage 2 from HEAD, and stage 3 from MERGE_HEAD (youcan inspect the stages with git ls-files -u). The workingtree files contain the result of the "merge" program; i.e. 3-waymerge results with familiar conflict markers .
When merging an annotated (and possibly signed) tag, Git alwayscreates a merge commit even if a fast-forward merge is possible, andthe commit message template is prepared with the tag message.Additionally, if the tag is signed, the signature check is reportedas a comment in the message template. See also git-tag.
Decide not to merge. The only clean-ups you need are to resetthe index file to the HEAD commit to reverse 2. and to cleanup working tree changes made by 2. and 3.; git merge --abortcan be used for this.
Resolve the conflicts. Git will mark the conflicts inthe working tree. Edit the files into shape andgit add them to the index. Use git commit orgit merge --continue to seal the deal. The latter commandchecks whether there is a (interrupted) merge in progressbefore calling git commit.
The merge mechanism (git merge and git pull commands) allows thebackend merge strategies to be chosen with -s option. Some strategiescan also take their own options, which can be passed by giving -Xarguments to git merge and/or git pull.
This option forces conflicting hunks to be auto-resolved cleanly byfavoring our version. Changes from the other tree that do notconflict with our side are reflected in the merge result.For a binary file, the entire contents are taken from our side.
This should not be confused with the ours merge strategy, which does noteven look at what the other tree contains at all. It discards everythingthe other tree did, declaring our history contains all that happened in it.
Treats lines with the indicated type of whitespace change asunchanged for the sake of a three-way merge. Whitespacechanges mixed with other changes to a line are not ignored.See also git-diff -b, -w,--ignore-space-at-eol, and --ignore-cr-at-eol.
This runs a virtual check-out and check-in of all three stagesof a file when resolving a three-way merge. This option ismeant to be used when merging branches with different cleanfilters or end-of-line normalization rules. See "Mergingbranches with differing checkin/checkout attributes" ingitattributes for details.
This can only resolve two heads using a 3-way mergealgorithm. When there is more than one commonancestor that can be used for 3-way merge, it creates amerged tree of the common ancestors and uses that asthe reference tree for the 3-way merge. This has beenreported to result in fewer merge conflicts withoutcausing mismerges by tests done on actual merge commitstaken from Linux 2.6 kernel development history.Additionally this can detect and handle merges involvingrenames. It does not make use of detected copies. This wasthe default strategy for resolving two heads from Git v0.99.9kuntil v2.33.0. 041b061a72