pgsql: Doc: include MERGE in variable substitution command list

Doc: include MERGE in variable substitution command list Backpatch to 15, where MERGE was introduced. Reported-by: Author: David Rowley Discussion: https://postgr.es/m/[email protected] Backpatch-through: 15 Branch -- REL_15_STABLE Details

pgsql: Doc: include MERGE in variable substitution command list

Doc: include MERGE in variable substitution command list Backpatch to 15, where MERGE was introduced. Reported-by: Author: David Rowley Discussion: https://postgr.es/m/[email protected] Backpatch-through: 15 Branch -- REL_16_STABLE Details

pgsql: Doc: include MERGE in variable substitution command list

Doc: include MERGE in variable substitution command list Backpatch to 15, where MERGE was introduced. Reported-by: Author: David Rowley Discussion: https://postgr.es/m/[email protected] Backpatch-through: 15 Branch -- REL_17_STABLE Details

pgsql: Doc: include MERGE in variable substitution command list

Doc: include MERGE in variable substitution command list Backpatch to 15, where MERGE was introduced. Reported-by: Author: David Rowley Discussion: https://postgr.es/m/[email protected] Backpatch-through: 15 Branch -- REL_18_STABLE Details

pgsql: Doc: include MERGE in variable substitution command list

Doc: include MERGE in variable substitution command list Backpatch to 15, where MERGE was introduced. Reported-by: Author: David Rowley Discussion: https://postgr.es/m/[email protected] Backpatch-through: 15 Branch -- master Details --- htt