alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these func- tions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity should not be the only index. A combination of the multicolumn index and a separate index on y would serve reasonably well. For queries involving only x, the multicolumn index could be used, though it would

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as col- umn aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity A combination of the 353 Chapter 11. Indexes multicolumn index and a separate index on y would serve reasonably well. For queries involving only x, the multicolumn index could be used, though it would

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as col- umn aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity should not be the only index. A combination of the multicolumn index and a separate index on y would serve reasonably well. For queries involving only x, the multicolumn index could be used, though it would

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these func- tions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these functions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity Function Description pg_create_physical_replication_slot ( slot_name name [, immediately_re- serve boolean, temporary boolean ] ) → record ( slot_name name, lsn pg_lsn ) Creates a new physical replication

alias list that could otherwise be attached to the FROM item; the names in the column definitions serve as column aliases. When using the ROWS FROM() syntax, a column_definition list can be attached to over direct use of these func- tions. However, because the concatenation operator is overloaded to serve all three cases, there are situations where use of one of the functions is helpful to avoid ambiguity SQL uses a three-valued logic system with true, false, and null, which represents “unknown”. Ob- serve the following truth tables: a b a AND b a OR b TRUE TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE